Convert.ToInt32 Convert.ToInt32 Convert.ToInt32 Convert.ToInt32 Method

Definizione

Converte un valore specificato in un intero con segno a 32 bit.Converts a specified value to a 32-bit signed integer.

Overload

ToInt32(Single) ToInt32(Single) ToInt32(Single) ToInt32(Single)

Converte il valore del numero a virgola mobile a precisione singola specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified single-precision floating-point number to an equivalent 32-bit signed integer.

ToInt32(String) ToInt32(String) ToInt32(String) ToInt32(String)

Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 32 bit equivalente.Converts the specified string representation of a number to an equivalent 32-bit signed integer.

ToInt32(UInt32) ToInt32(UInt32) ToInt32(UInt32) ToInt32(UInt32)

Converte il valore dell'intero senza segno a 32 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 32-bit unsigned integer to an equivalent 32-bit signed integer.

ToInt32(SByte) ToInt32(SByte) ToInt32(SByte) ToInt32(SByte)

Converte il valore dell'intero con segno a 8 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 8-bit signed integer to the equivalent 32-bit signed integer.

ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider)

Converte il valore dell'oggetto specificato in un intero con segno a 32 bit mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the value of the specified object to a 32-bit signed integer, using the specified culture-specific formatting information.

ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider)

Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 32 bit equivalente mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the specified string representation of a number to an equivalent 32-bit signed integer, using the specified culture-specific formatting information.

ToInt32(String, Int32) ToInt32(String, Int32) ToInt32(String, Int32) ToInt32(String, Int32)

Converte la rappresentazione di stringa di un numero in una base specificata nell'intero con segno a 32 bit equivalente.Converts the string representation of a number in a specified base to an equivalent 32-bit signed integer.

ToInt32(UInt64) ToInt32(UInt64) ToInt32(UInt64) ToInt32(UInt64)

Converte il valore dell'intero senza segno a 64 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 64-bit unsigned integer to an equivalent 32-bit signed integer.

ToInt32(Object) ToInt32(Object) ToInt32(Object) ToInt32(Object)

Converte il valore dell'oggetto specificato in un intero con segno a 32 bit.Converts the value of the specified object to a 32-bit signed integer.

ToInt32(UInt16) ToInt32(UInt16) ToInt32(UInt16) ToInt32(UInt16)

Converte il valore dell'intero senza segno a 16 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 16-bit unsigned integer to the equivalent 32-bit signed integer.

ToInt32(Int32) ToInt32(Int32) ToInt32(Int32) ToInt32(Int32)

Restituisce l'intero con segno a 32 bit specificato; non viene eseguita alcuna conversione effettiva.Returns the specified 32-bit signed integer; no actual conversion is performed.

ToInt32(Byte) ToInt32(Byte) ToInt32(Byte) ToInt32(Byte)

Converte il valore dell'intero senza segno a 8 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 8-bit unsigned integer to the equivalent 32-bit signed integer.

ToInt32(Char) ToInt32(Char) ToInt32(Char) ToInt32(Char)

Converte il valore del carattere Unicode specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified Unicode character to the equivalent 32-bit signed integer.

ToInt32(DateTime) ToInt32(DateTime) ToInt32(DateTime) ToInt32(DateTime)

La chiamata di questo metodo genera sempre un'eccezione InvalidCastException.Calling this method always throws InvalidCastException.

ToInt32(Boolean) ToInt32(Boolean) ToInt32(Boolean) ToInt32(Boolean)

Converte il valore booleano specificato nell'intero con segno a 32 bit equivalente.Converts the specified Boolean value to the equivalent 32-bit signed integer.

ToInt32(Int64) ToInt32(Int64) ToInt32(Int64) ToInt32(Int64)

Converte il valore dell'intero con segno a 64 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 64-bit signed integer to an equivalent 32-bit signed integer.

ToInt32(Double) ToInt32(Double) ToInt32(Double) ToInt32(Double)

Converte il valore del numero a virgola mobile a precisione doppia specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified double-precision floating-point number to an equivalent 32-bit signed integer.

ToInt32(Int16) ToInt32(Int16) ToInt32(Int16) ToInt32(Int16)

Converte il valore dell'intero con segno a 16 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 16-bit signed integer to an equivalent 32-bit signed integer.

ToInt32(Decimal) ToInt32(Decimal) ToInt32(Decimal) ToInt32(Decimal)

Converte il valore del numero decimale specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified decimal number to an equivalent 32-bit signed integer.

ToInt32(Single) ToInt32(Single) ToInt32(Single) ToInt32(Single)

Converte il valore del numero a virgola mobile a precisione singola specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified single-precision floating-point number to an equivalent 32-bit signed integer.

public:
 static int ToInt32(float value);
public static int ToInt32 (float value);
static member ToInt32 : single -> int
Public Shared Function ToInt32 (value As Single) As Integer

Parametri

value
Single Single Single Single

Numero a virgola mobile a precisione singola da convertire.The single-precision floating-point number to convert.

Restituisce

value, arrotondato all'intero con segno a 32 bit più vicino.value, rounded to the nearest 32-bit signed integer. Se value si trova a metà tra due numeri interi, viene restituito il numero intero pari; vale a dire, 4,5 viene convertito in 4, mentre 5,5 viene convertito in 6.If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

Eccezioni

value è maggiore di MaxValue o minore di MinValue.value is greater than MaxValue or less than MinValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento in una matrice di Single valori in un numero intero.The following example attempts to convert each element in an array of Single values to an integer.

float[] values= { Single.MinValue, -1.38e10f, -1023.299f, -12.98f,
                  0f, 9.113e-16f, 103.919f, 17834.191f, Single.MaxValue };
int result;

foreach (float value in values)
{
   try {
      result = Convert.ToInt32(value);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        value.GetType().Name, value, result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the Int32 type.", value);
   }   
}                                 
// The example displays the following output:
//    -3.40282346638529E+38 is outside the range of the Int32 type.
//    -13799999488 is outside the range of the Int32 type.
//    Converted the Double value -1023.29901123047 to the Int32 value -1023.
//    Converted the Double value -12.9799995422363 to the Int32 value -13.
//    Converted the Double value 0 to the Int32 value 0.
//    Converted the Double value 9.11299983940444E-16 to the Int32 value 0.
//    Converted the Double value 103.918998718262 to the Int32 value 104.
//    Converted the Double value 17834.19140625 to the Int32 value 17834.
//    3.40282346638529E+38 is outside the range of the Int32 type.
Dim values() As Single = { Single.MinValue, -1.38e10, -1023.299, -12.98, _
                           0, 9.113e-16, 103.919, 17834.191, Single.MaxValue }
Dim result As Integer

For Each value As Single In values
   Try
      result = Convert.ToInt32(value)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        value.GetType().Name, value, result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the Int32 type.", value)
   End Try   
Next                                 
' The example displays the following output:
'    -3.40282346638529E+38 is outside the range of the Int32 type.
'    -13799999488 is outside the range of the Int32 type.
'    Converted the Double value -1023.29901123047 to the Int32 value -1023.
'    Converted the Double value -12.9799995422363 to the Int32 value -13.
'    Converted the Double value 0 to the Int32 value 0.
'    Converted the Double value 9.11299983940444E-16 to the Int32 value 0.
'    Converted the Double value 103.918998718262 to the Int32 value 104.
'    Converted the Double value 17834.19140625 to the Int32 value 17834.
'    3.40282346638529E+38 is outside the range of the Int32 type.
Vedi anche

ToInt32(String) ToInt32(String) ToInt32(String) ToInt32(String)

Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 32 bit equivalente.Converts the specified string representation of a number to an equivalent 32-bit signed integer.

public:
 static int ToInt32(System::String ^ value);
public static int ToInt32 (string value);
static member ToInt32 : string -> int
Public Shared Function ToInt32 (value As String) As Integer

Parametri

value
String String String String

Stringa che contiene il numero da convertire.A string that contains the number to convert.

Restituisce

Intero con segno a 32 bit equivalente al numero in value oppure 0 (zero) se value è null.A 32-bit signed integer that is equivalent to the number in value, or 0 (zero) if value is null.

Eccezioni

value non è costituito da un segno facoltativo seguito da una sequenza di cifre (da 0 a 9).value does not consist of an optional sign followed by a sequence of digits (0 through 9).

L'oggetto value rappresenta un numero minore di MinValue o maggiore di MaxValue.value represents a number that is less than MinValue or greater than MaxValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento in una matrice di stringhe numeriche in un numero intero.The following example attempts to convert each element in a numeric string array to an integer.

string[] values = { "One", "1.34e28", "-26.87", "-18", "-6.00",
                    " 0", "137", "1601.9", Int32.MaxValue.ToString() };
int result;

foreach (string value in values)
{
   try {
      result = Convert.ToInt32(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value, result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the Int32 type.", value);
   }   
   catch (FormatException) {
      Console.WriteLine("The {0} value '{1}' is not in a recognizable format.",
                        value.GetType().Name, value);
   }   
}                                 
// The example displays the following output:
//    The String value 'One' is not in a recognizable format.
//    The String value '1.34e28' is not in a recognizable format.
//    The String value '-26.87' is not in a recognizable format.
//    Converted the String value '-18' to the Int32 value -18.
//    The String value '-6.00' is not in a recognizable format.
//    Converted the String value ' 0' to the Int32 value 0.
//    Converted the String value '137' to the Int32 value 137.
//    The String value '1601.9' is not in a recognizable format.
//    Converted the String value '2147483647' to the Int32 value 2147483647.
Dim values() As String = { "One", "1.34e28", "-26.87", "-18", "-6.00", _
                           " 0", "137", "1601.9", Int32.MaxValue.ToString() }
Dim result As Integer

For Each value As String In values
   Try
      result = Convert.ToInt32(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the Int32 type.", value)
   Catch e As FormatException
      Console.WriteLine("The {0} value '{1}' is not in a recognizable format.", _
                        value.GetType().Name, value)
   End Try   
Next                                 
' The example displays the following output:
'    The String value 'One' is not in a recognizable format.
'    The String value '1.34e28' is not in a recognizable format.
'    The String value '-26.87' is not in a recognizable format.
'    Converted the String value '-18' to the Int32 value -18.
'    The String value '-6.00' is not in a recognizable format.
'    Converted the String value ' 0' to the Int32 value 0.
'    Converted the String value '137' to the Int32 value 137.
'    The String value '1601.9' is not in a recognizable format.
'    Converted the String value '2147483647' to the Int32 value 2147483647.

Commenti

Usando il ToInt32(String) metodo equivale a passare value per il Int32.Parse(String) (metodo).valueUsing the ToInt32(String) method is equivalent to passing value to the Int32.Parse(String) method.value viene interpretata usando le convenzioni di formattazione delle impostazioni cultura del thread corrente.is interpreted by using the formatting conventions of the current thread culture.

Se si preferisce non gestire un'eccezione se la conversione non riesce, è possibile chiamare il Int32.TryParse metodo invece.If you prefer not to handle an exception if the conversion fails, you can call the Int32.TryParse method instead. Restituisce un Boolean valore che indica se la conversione ha avuto esito positivo o negativo.It returns a Boolean value that indicates whether the conversion succeeded or failed.

ToInt32(UInt32) ToInt32(UInt32) ToInt32(UInt32) ToInt32(UInt32)

Importante

Questa API non è conforme a CLS.

Converte il valore dell'intero senza segno a 32 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 32-bit unsigned integer to an equivalent 32-bit signed integer.

public:
 static int ToInt32(System::UInt32 value);
[System.CLSCompliant(false)]
public static int ToInt32 (uint value);
static member ToInt32 : uint32 -> int
Public Shared Function ToInt32 (value As UInteger) As Integer

Parametri

value
UInt32 UInt32 UInt32 UInt32

Intero senza segno a 32 bit da convertire.The 32-bit unsigned integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Eccezioni

Esempi

Nell'esempio seguente prova a convertire ogni elemento in una matrice di interi senza segno in un intero con segno.The following example attempts to convert each element in an array of unsigned integers to a signed integer.

uint[] numbers = { UInt32.MinValue, 121, 340, UInt32.MaxValue };
int result;
foreach (uint number in numbers)
{
   try {
      result = Convert.ToInt32(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    Converted the UInt32 value 0 to the Int32 value 0.
//    Converted the UInt32 value 121 to the Int32 value 121.
//    Converted the UInt32 value 340 to the Int32 value 340.
//    The UInt32 value 4294967295 is outside the range of the Int32 type.
Dim numbers() As UInteger = { UInt32.MinValue, 121, 340, UInt32.MaxValue }
Dim result As Integer
For Each number As UInteger In numbers
   Try
      result = Convert.ToInt32(number)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    Converted the UInt32 value 0 to the Int32 value 0.
'    Converted the UInt32 value 121 to the Int32 value 121.
'    Converted the UInt32 value 340 to the Int32 value 340.
'    The UInt32 value 4294967295 is outside the range of the Int32 type.

ToInt32(SByte) ToInt32(SByte) ToInt32(SByte) ToInt32(SByte)

Importante

Questa API non è conforme a CLS.

Converte il valore dell'intero con segno a 8 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 8-bit signed integer to the equivalent 32-bit signed integer.

public:
 static int ToInt32(System::SByte value);
[System.CLSCompliant(false)]
public static int ToInt32 (sbyte value);
static member ToInt32 : sbyte -> int
Public Shared Function ToInt32 (value As SByte) As Integer

Parametri

value
SByte SByte SByte SByte

Intero con segno a 8 bit da convertire.The 8-bit signed integer to convert.

Restituisce

Intero con segno a 8 bit equivalente a value.A 8-bit signed integer that is equivalent to value.

Esempi

Nell'esempio seguente converte ogni elemento in una matrice di byte con segno in un intero.The following example converts each element in an array of signed bytes to an integer.

sbyte[] numbers = { SByte.MinValue, -1, 0, 10, SByte.MaxValue };
int result;

foreach (sbyte number in numbers)
{
   result = Convert.ToInt32(number);
   Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                     number.GetType().Name, number,
                     result.GetType().Name, result);
}
// The example displays the following output:
//       Converted the SByte value -128 to the Int32 value -128.
//       Converted the SByte value -1 to the Int32 value -1.
//       Converted the SByte value 0 to the Int32 value 0.
//       Converted the SByte value 10 to the Int32 value 10.
//       Converted the SByte value 127 to the Int32 value 127.
Dim numbers() As SByte = { SByte.MinValue, -1, 0, 10, SByte.MaxValue }
Dim result As Integer

For Each number As SByte In numbers
   result = Convert.ToInt32(number)
   Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                     number.GetType().Name, number, _
                     result.GetType().Name, result)
Next
' The example displays the following output:
'       Converted the SByte value -128 to the Int32 value -128.
'       Converted the SByte value -1 to the Int32 value -1.
'       Converted the SByte value 0 to the Int32 value 0.
'       Converted the SByte value 10 to the Int32 value 10.
'       Converted the SByte value 127 to the Int32 value 127.

ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider) ToInt32(Object, IFormatProvider)

Converte il valore dell'oggetto specificato in un intero con segno a 32 bit mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the value of the specified object to a 32-bit signed integer, using the specified culture-specific formatting information.

public:
 static int ToInt32(System::Object ^ value, IFormatProvider ^ provider);
public static int ToInt32 (object value, IFormatProvider provider);
static member ToInt32 : obj * IFormatProvider -> int
Public Shared Function ToInt32 (value As Object, provider As IFormatProvider) As Integer

Parametri

value
Object Object Object Object

Oggetto che implementa l'interfaccia IConvertible.An object that implements the IConvertible interface.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

Oggetto che fornisce informazioni di formattazione specifiche delle impostazioni cultura.An object that supplies culture-specific formatting information.

Restituisce

Intero con segno a 32 bit equivalente a value oppure zero se value è null.A 32-bit signed integer that is equivalent to value, or zero if value is null.

Eccezioni

Il formato di value non è appropriato.value is not in an appropriate format.

L'oggetto value rappresenta un numero minore di MinValue o maggiore di MaxValue.value represents a number that is less than MinValue or greater than MaxValue.

Esempi

L'esempio seguente definisce una classe che implementa IConvertible e una classe che implementa IFormatProvider.The following example defines a class that implements IConvertible and a class that implements IFormatProvider. Gli oggetti della classe che implementa IConvertible contengono una matrice di Double valori.Objects of the class that implements IConvertible hold an array of Double values. Viene passato un oggetto di ogni classe per il ToInt32 (metodo).An object of each class is passed to the ToInt32 method. Questo metodo restituisce una media della matrice di Double valori, utilizzando l'oggetto che implementa IFormatProvider per determinare la modalità calcolare la Media.This method returns an average of the array of Double values, using the object that implements IFormatProvider to determine how to calculate the average.

using namespace System;
using namespace System::Collections;

// Define the types of averaging available in the class 
// implementing IConvertible.
public enum class AverageType : short
{
   None = 0,
   GeometricMean = 1,
   ArithmeticMean = 2,
   Median = 3
};


// Pass an instance of this class to methods that require an 
// IFormatProvider. The class instance determines the type of 
// average to calculate.
ref class AverageInfo: public IFormatProvider
{
protected:
   AverageType AvgType;

public:

   // Specify the type of averaging in the constructor.
   AverageInfo( AverageType avgType )
   {
      this->AvgType = avgType;
   }


   // This method returns a reference to the containing object 
   // if an object of AverageInfo type is requested. 
   virtual Object^ GetFormat( Type^ argType )
   {
      if ( argType == AverageInfo::typeid)
            return this;
      else
            return (Object^)0;
   }


   property AverageType TypeOfAverage 
   {

      // Use this property to set or get the type of averaging.
      AverageType get()
      {
         return this->AvgType;
      }

      void set( AverageType value )
      {
         this->AvgType = value;
      }

   }

};


// This class encapsulates an array of double values and implements 
// the IConvertible interface. Most of the IConvertible methods 
// return an average of the array elements in one of three types: 
// arithmetic mean, geometric mean, or median. 
ref class DataSet: public IConvertible
{
private:
   static Object^ null = nullptr;

protected:
   ArrayList^ data;
   AverageInfo^ defaultProvider;

   // This method unboxes a boxed double.
   double UnBoxDouble( Object^ obj )
   {
      return  *static_cast<double^>(obj);
   }


public:

   // Construct the object and add an initial list of values.
   // Create a default format provider.
   DataSet( ... array<Double>^values )
   {
      data = gcnew ArrayList( (Array^)values );
      defaultProvider = gcnew AverageInfo( AverageType::ArithmeticMean );
   }


   // Add additional values with this method.
   int Add( double value )
   {
      data->Add( value );
      return data->Count;
   }


   property double Item[ int ]
   {

      // Get, set, and add values with this indexer property.
      double get( int index )
      {
         if ( index >= 0 && index < data->Count )
                  return UnBoxDouble( data[ index ] );
         else
                  throw gcnew InvalidOperationException( "[DataSet.get] Index out of range." );
      }

      void set( int index, double value )
      {
         if ( index >= 0 && index < data->Count )
                  data[ index ] = value;
         else
         if ( index == data->Count )
                  data->Add( value );
         else
                  throw gcnew InvalidOperationException( "[DataSet.set] Index out of range." );
      }

   }

   property int Count 
   {

      // This property returns the number of elements in the object.
      int get()
      {
         return data->Count;
      }

   }

protected:

   // This method calculates the average of the object's elements.
   double Average( AverageType avgType )
   {
      double SumProd;
      if ( data->Count == 0 )
            return 0.0;

      switch ( avgType )
      {
         case AverageType::GeometricMean:
            SumProd = 1.0;
            for ( int Index = 0; Index < data->Count; Index++ )
               SumProd *= UnBoxDouble( data[ Index ] );
            
            // This calculation will not fail with negative 
            // elements.
            return Math::Sign( SumProd ) * Math::Pow( Math::Abs( SumProd ), 1.0 / data->Count );

         case AverageType::ArithmeticMean:
            SumProd = 0.0;
            for ( int Index = 0; Index < data->Count; Index++ )
               SumProd += UnBoxDouble( data[ Index ] );
            return SumProd / data->Count;

         case AverageType::Median:
            if ( data->Count % 2 == 0 )
                        return (UnBoxDouble( data[ data->Count / 2 ] ) + UnBoxDouble( data[ data->Count / 2 - 1 ] )) / 2.0;
            else
                        return UnBoxDouble( data[ data->Count / 2 ] );

         default:
            return 0.0;
      }
   }


   // Get the AverageInfo object from the caller's format provider,
   // or use the local default.
   AverageInfo^ GetAverageInfo( IFormatProvider^ provider )
   {
      AverageInfo^ avgInfo = nullptr;
      if ( provider != nullptr )
            avgInfo = static_cast<AverageInfo^>(provider->GetFormat( AverageInfo::typeid ));

      if ( avgInfo == nullptr )
            return defaultProvider;
      else
            return avgInfo;
   }


   // Calculate the average and limit the range.
   double CalcNLimitAverage( double min, double max, IFormatProvider^ provider )
   {
      
      // Get the format provider and calculate the average.
      AverageInfo^ avgInfo = GetAverageInfo( provider );
      double avg = Average( avgInfo->TypeOfAverage );
      
      // Limit the range, based on the minimum and maximum values 
      // for the type.
      return avg > max ? max : avg < min ? min : avg;
   }


public:

   // The following elements are required by IConvertible.
   // None of these conversion functions throw exceptions. When
   // the data is out of range for the type, the appropriate
   // MinValue or MaxValue is used.
   virtual TypeCode GetTypeCode()
   {
      return TypeCode::Object;
   }

   virtual bool ToBoolean( IFormatProvider^ provider )
   {
      
      // ToBoolean is false if the dataset is empty.
      if ( data->Count <= 0 )
            return false;
      // For median averaging, ToBoolean is true if any 
      // non-discarded elements are nonzero.
      else
      
      // For median averaging, ToBoolean is true if any 
      // non-discarded elements are nonzero.
      if ( AverageType::Median == GetAverageInfo( provider )->TypeOfAverage )
      {
         if ( data->Count % 2 == 0 )
                  return (UnBoxDouble( data[ data->Count / 2 ] ) != 0.0 || UnBoxDouble( data[ data->Count / 2 - 1 ] ) != 0.0);
         else
                  return UnBoxDouble( data[ data->Count / 2 ] ) != 0.0;
      }
      // For arithmetic or geometric mean averaging, ToBoolean is 
      // true if any element of the dataset is nonzero.  
      else
      {
         for ( int Index = 0; Index < data->Count; Index++ )
            if ( UnBoxDouble( data[ Index ] ) != 0.0 )
                        return true;
         return false;
      }
   }

   virtual Byte ToByte( IFormatProvider^ provider )
   {
      return Convert::ToByte( CalcNLimitAverage( Byte::MinValue, Byte::MaxValue, provider ) );
   }

   virtual Char ToChar( IFormatProvider^ provider )
   {
      return Convert::ToChar( Convert::ToUInt16( CalcNLimitAverage( Char::MinValue, Char::MaxValue, provider ) ) );
   }


   // Convert to DateTime by adding the calculated average as 
   // seconds to the current date and time. A valid DateTime is 
   // always returned.
   virtual DateTime ToDateTime( IFormatProvider^ provider )
   {
      double seconds = Average( GetAverageInfo( provider )->TypeOfAverage );
      try
      {
         return DateTime::Now.AddSeconds( seconds );
      }
      catch ( ArgumentOutOfRangeException^ ) 
      {
         return seconds < 0.0 ? DateTime::MinValue : DateTime::MaxValue;
      }

   }

   virtual Decimal ToDecimal( IFormatProvider^ provider )
   {
      
      // The Double conversion rounds Decimal.MinValue and 
      // Decimal.MaxValue to invalid Decimal values, so the 
      // following limits must be used.
      return Convert::ToDecimal( CalcNLimitAverage(  -79228162514264330000000000000.0, 79228162514264330000000000000.0, provider ) );
   }

   virtual double ToDouble( IFormatProvider^ provider )
   {
      return Average( GetAverageInfo( provider )->TypeOfAverage );
   }

   virtual short ToInt16( IFormatProvider^ provider )
   {
      return Convert::ToInt16( CalcNLimitAverage( Int16::MinValue, Int16::MaxValue, provider ) );
   }

   virtual int ToInt32( IFormatProvider^ provider )
   {
      return Convert::ToInt32( CalcNLimitAverage( Int32::MinValue, Int32::MaxValue, provider ) );
   }

   virtual __int64 ToInt64( IFormatProvider^ provider )
   {
      
      // The Double conversion rounds Int64.MinValue and 
      // Int64.MaxValue to invalid Int64 values, so the following 
      // limits must be used.
      return Convert::ToInt64( CalcNLimitAverage(  -9223372036854775000, 9223372036854775000, provider ) );
   }

   virtual signed char ToSByte( IFormatProvider^ provider )
   {
      return Convert::ToSByte( CalcNLimitAverage( SByte::MinValue, SByte::MaxValue, provider ) );
   }

   virtual float ToSingle( IFormatProvider^ provider )
   {
      return Convert::ToSingle( CalcNLimitAverage( Single::MinValue, Single::MaxValue, provider ) );
   }

   virtual UInt16 ToUInt16( IFormatProvider^ provider )
   {
      return Convert::ToUInt16( CalcNLimitAverage( UInt16::MinValue, UInt16::MaxValue, provider ) );
   }

   virtual UInt32 ToUInt32( IFormatProvider^ provider )
   {
      return Convert::ToUInt32( CalcNLimitAverage( UInt32::MinValue, UInt32::MaxValue, provider ) );
   }

   virtual UInt64 ToUInt64( IFormatProvider^ provider )
   {
      
      // The Double conversion rounds UInt64.MaxValue to an invalid
      // UInt64 value, so the following limit must be used.
      return Convert::ToUInt64( CalcNLimitAverage( 0, 18446744073709550000.0, provider ) );
   }

   virtual Object^ ToType( Type^ conversionType, IFormatProvider^ provider )
   {
      return Convert::ChangeType( Average( GetAverageInfo( provider )->TypeOfAverage ), conversionType );
   }

   virtual String^ ToString( IFormatProvider^ provider )
   {
      AverageType avgType = GetAverageInfo( provider )->TypeOfAverage;
      return String::Format( "( {0}: {1:G10} )", avgType, Average( avgType ) );
   }

};


// Display a DataSet with three different format providers.
void DisplayDataSet( DataSet^ ds )
{
   IFormatProvider^ null = nullptr;
   String^ fmt = "{0,-12}{1,20}{2,20}{3,20}";
   AverageInfo^ median = gcnew AverageInfo( AverageType::Median );
   AverageInfo^ geMean = gcnew AverageInfo( AverageType::GeometricMean );
   
   // Display the dataset elements.
   if ( ds->Count > 0 )
   {
      Console::Write( "\nDataSet: [{0}", ds->Item[ 0 ] );
      for ( int iX = 1; iX < ds->Count; iX++ )
         Console::Write( ", {0}", ds->Item[ iX ] );
      Console::WriteLine( "]\n" );
   }

   Console::WriteLine( fmt, "Convert::", "Default", "Geometric Mean", "Median" );
   Console::WriteLine( fmt, "---------", "-------", "--------------", "------" );
   Console::WriteLine( fmt, "ToBoolean", Convert::ToBoolean( ds, null ), Convert::ToBoolean( ds, geMean ), Convert::ToBoolean( ds, median ) );
   Console::WriteLine( fmt, "ToByte", Convert::ToByte( ds, null ), Convert::ToByte( ds, geMean ), Convert::ToByte( ds, median ) );
   Console::WriteLine( fmt, "ToChar", Convert::ToChar( ds, null ), Convert::ToChar( ds, geMean ), Convert::ToChar( ds, median ) );
   Console::WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}"
   "{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}", "ToDateTime", Convert::ToDateTime( ds, null ), Convert::ToDateTime( ds, geMean ), Convert::ToDateTime( ds, median ) );
   Console::WriteLine( fmt, "ToDecimal", Convert::ToDecimal( ds, null ), Convert::ToDecimal( ds, geMean ), Convert::ToDecimal( ds, median ) );
   Console::WriteLine( fmt, "ToDouble", Convert::ToDouble( ds, null ), Convert::ToDouble( ds, geMean ), Convert::ToDouble( ds, median ) );
   Console::WriteLine( fmt, "ToInt16", Convert::ToInt16( ds, null ), Convert::ToInt16( ds, geMean ), Convert::ToInt16( ds, median ) );
   Console::WriteLine( fmt, "ToInt32", Convert::ToInt32( ds, null ), Convert::ToInt32( ds, geMean ), Convert::ToInt32( ds, median ) );
   Console::WriteLine( fmt, "ToInt64", Convert::ToInt64( ds, null ), Convert::ToInt64( ds, geMean ), Convert::ToInt64( ds, median ) );
   Console::WriteLine( fmt, "ToSByte", Convert::ToSByte( ds, null ), Convert::ToSByte( ds, geMean ), Convert::ToSByte( ds, median ) );
   Console::WriteLine( fmt, "ToSingle", Convert::ToSingle( ds, null ), Convert::ToSingle( ds, geMean ), Convert::ToSingle( ds, median ) );
   Console::WriteLine( fmt, "ToUInt16", Convert::ToUInt16( ds, null ), Convert::ToUInt16( ds, geMean ), Convert::ToUInt16( ds, median ) );
   Console::WriteLine( fmt, "ToUInt32", Convert::ToUInt32( ds, null ), Convert::ToUInt32( ds, geMean ), Convert::ToUInt32( ds, median ) );
   Console::WriteLine( fmt, "ToUInt64", Convert::ToUInt64( ds, null ), Convert::ToUInt64( ds, geMean ), Convert::ToUInt64( ds, median ) );
}

int main()
{
   Console::WriteLine( "This example of the "
   "Convert::To<Type>( Object*, IFormatProvider* ) methods "
   "\ngenerates the following output. The example "
   "displays the values \nreturned by the methods, "
   "using several IFormatProvider objects.\n" );
   
   // To call a [ParamArray] method in C++, you cannot just
   // list the parameters, you need to build an array.
   array<Double>^dataElem = gcnew array<Double>(6);
   dataElem[ 0 ] = 10.5;
   dataElem[ 1 ] = 22.2;
   dataElem[ 2 ] = 45.9;
   dataElem[ 3 ] = 88.7;
   dataElem[ 4 ] = 156.05;
   dataElem[ 5 ] = 297.6;
   DataSet^ ds1 = gcnew DataSet( dataElem );
   DisplayDataSet( ds1 );
   dataElem = gcnew array<Double>(5);
   dataElem[ 0 ] = 359999.95;
   dataElem[ 1 ] = 425000;
   dataElem[ 2 ] = 499999.5;
   dataElem[ 3 ] = 775000;
   dataElem[ 4 ] = 1695000;
   DataSet^ ds2 = gcnew DataSet( dataElem );
   DisplayDataSet( ds2 );
}

/*
This example of the Convert::To<Type>( Object*, IFormatProvider* ) methods
generates the following output. The example displays the values
returned by the methods, using several IFormatProvider objects.

DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]

Convert::                Default      Geometric Mean              Median
---------                -------      --------------              ------
ToBoolean                   True                True                True
ToByte                       103                  59                  67
ToChar                         g                   ;                   C
ToDateTime   2003-05-13 15:30:23 2003-05-13 15:29:39 2003-05-13 15:29:47
ToDecimal       103.491666666667    59.4332135445164                67.3
ToDouble        103.491666666667    59.4332135445164                67.3
ToInt16                      103                  59                  67
ToInt32                      103                  59                  67
ToInt64                      103                  59                  67
ToSByte                      103                  59                  67
ToSingle                103.4917            59.43321                67.3
ToUInt16                     103                  59                  67
ToUInt32                     103                  59                  67
ToUInt64                     103                  59                  67

DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]

Convert::                Default      Geometric Mean              Median
---------                -------      --------------              ------
ToBoolean                   True                True                True
ToByte                       255                 255                 255
ToChar                         ?                   ?                   ?
ToDateTime   2003-05-22 08:05:19 2003-05-20 22:54:57 2003-05-19 10:21:59
ToDecimal              750999.89    631577.237188435            499999.5
ToDouble               750999.89    631577.237188435            499999.5
ToInt16                    32767               32767               32767
ToInt32                   751000              631577              500000
ToInt64                   751000              631577              500000
ToSByte                      127                 127                 127
ToSingle                750999.9            631577.3            499999.5
ToUInt16                   65535               65535               65535
ToUInt32                  751000              631577              500000
ToUInt64                  751000              631577              500000
*/
using System;
using System.Collections;

// Define the types of averaging available in the class 
// implementing IConvertible.
public enum AverageType : short
{
    None = 0,
    GeometricMean = 1,
    ArithmeticMean = 2,
    Median = 3
};

// Pass an instance of this class to methods that require an 
// IFormatProvider. The class instance determines the type of 
// average to calculate.
public class AverageInfo : IFormatProvider
{
    protected AverageType AvgType;

    // Specify the type of averaging in the constructor.
    public AverageInfo( AverageType avgType )
    {
        this.AvgType = avgType;
    }

    // This method returns a reference to the containing object 
    // if an object of AverageInfo type is requested. 
    public object GetFormat( Type argType )
    {
        if ( argType == typeof( AverageInfo ) )
            return this;
        else
            return null;
    }

    // Use this property to set or get the type of averaging.
    public AverageType TypeOfAverage        
    {
        get { return this.AvgType; }
        set { this.AvgType = value; }
    }
}

// This class encapsulates an array of double values and implements 
// the IConvertible interface. Most of the IConvertible methods 
// return an average of the array elements in one of three types: 
// arithmetic mean, geometric mean, or median. 
public class DataSet : IConvertible
{
    protected ArrayList     data;
    protected AverageInfo   defaultProvider;
        
    // Construct the object and add an initial list of values.
    // Create a default format provider.
    public DataSet( params double[ ] values )
    {
        data = new ArrayList( values );
        defaultProvider = 
            new AverageInfo( AverageType.ArithmeticMean );
    }
        
    // Add additional values with this method.
    public int Add( double value )
    {
        data.Add( value );
        return data.Count;
    }
        
    // Get, set, and add values with this indexer property.
    public double this[ int index ]        
    {
        get
        {
            if( index >= 0 && index < data.Count )
                return (double)data[ index ];
            else
                throw new InvalidOperationException(
                    "[DataSet.get] Index out of range." );
        }
        set
        {
            if( index >= 0 && index < data.Count )
                data[ index ] = value;

            else if( index == data.Count )
                data.Add( value );
            else
                throw new InvalidOperationException(
                    "[DataSet.set] Index out of range." );
        }
    }
        
    // This property returns the number of elements in the object.
    public int Count        
    {
        get { return data.Count; }
    }

    // This method calculates the average of the object's elements.
    protected double Average( AverageType avgType )
    {
        double  SumProd;

        if( data.Count == 0 ) 
            return 0.0;

        switch( avgType )
        {
            case AverageType.GeometricMean:

                SumProd = 1.0;
                for( int Index = 0; Index < data.Count; Index++ )
                    SumProd *= (double)data[ Index ];
                
                // This calculation will not fail with negative 
                // elements.
                return Math.Sign( SumProd ) * Math.Pow( 
                    Math.Abs( SumProd ), 1.0 / data.Count );

            case AverageType.ArithmeticMean:

                SumProd = 0.0;
                for( int Index = 0; Index < data.Count; Index++ )
                    SumProd += (double)data[ Index ];

                return SumProd / data.Count;

            case AverageType.Median:

                if( data.Count % 2 == 0 )
                    return ( (double)data[ data.Count / 2 ] + 
                        (double)data[ data.Count / 2 - 1 ] ) / 2.0;
                else
                    return (double)data[ data.Count / 2 ];

            default:
                return 0.0;
        }
    }

    // Get the AverageInfo object from the caller's format provider,
    // or use the local default.
    protected AverageInfo GetAverageInfo( IFormatProvider provider )
    {
        AverageInfo avgInfo = null;

        if( provider != null )
            avgInfo = (AverageInfo)provider.GetFormat( 
                typeof( AverageInfo ) );

        if ( avgInfo == null )
            return defaultProvider;
        else
            return avgInfo;
    }

    // Calculate the average and limit the range.
    protected double CalcNLimitAverage( double min, double max, 
        IFormatProvider provider )
    {
        // Get the format provider and calculate the average.
        AverageInfo avgInfo = GetAverageInfo( provider );
        double avg = Average( avgInfo.TypeOfAverage );

        // Limit the range, based on the minimum and maximum values 
        // for the type.
        return avg > max ? max : avg < min ? min : avg;

    }

    // The following elements are required by IConvertible.

    // None of these conversion functions throw exceptions. When
    // the data is out of range for the type, the appropriate
    // MinValue or MaxValue is used.
    public TypeCode GetTypeCode( )
    {
        return TypeCode.Object;
    }

    public bool ToBoolean( IFormatProvider provider )
    {
        // ToBoolean is false if the dataset is empty.
        if( data.Count <= 0 )
            return false;

        // For median averaging, ToBoolean is true if any 
        // non-discarded elements are nonzero.
        else if( AverageType.Median == 
            GetAverageInfo( provider ).TypeOfAverage )
        {
            if (data.Count % 2 == 0 )
                return ( (double)data[ data.Count / 2 ] != 0.0 || 
                    (double)data[ data.Count / 2 - 1 ] != 0.0 );
            else
                return (double)data[ data.Count / 2 ] != 0.0;
        }

        // For arithmetic or geometric mean averaging, ToBoolean is 
        // true if any element of the dataset is nonzero.  
        else
        {
            for( int Index = 0; Index < data.Count; Index++ )
                if( (double)data[ Index ] != 0.0 ) 
                    return true;
            return false;
        }
    }

    public byte ToByte( IFormatProvider provider )
    {
        return Convert.ToByte( CalcNLimitAverage( 
            Byte.MinValue, Byte.MaxValue, provider ) );
    }

    public char ToChar( IFormatProvider provider )
    {
        return Convert.ToChar( Convert.ToUInt16( CalcNLimitAverage( 
            Char.MinValue, Char.MaxValue, provider ) ) );
    }

    // Convert to DateTime by adding the calculated average as 
    // seconds to the current date and time. A valid DateTime is 
    // always returned.
    public DateTime ToDateTime( IFormatProvider provider )
    {
        double seconds = 
            Average( GetAverageInfo( provider ).TypeOfAverage );
        try
        {
            return DateTime.Now.AddSeconds( seconds );
        }
        catch( ArgumentOutOfRangeException )
        {
            return seconds < 0.0 ? DateTime.MinValue : DateTime.MaxValue;
        }
    }

    public decimal ToDecimal( IFormatProvider provider )
    {
        // The Double conversion rounds Decimal.MinValue and 
        // Decimal.MaxValue to invalid Decimal values, so the 
        // following limits must be used.
        return Convert.ToDecimal( CalcNLimitAverage( 
            -79228162514264330000000000000.0, 
            79228162514264330000000000000.0, provider ) );
    }

    public double ToDouble( IFormatProvider provider )
    {
        return Average( GetAverageInfo(provider).TypeOfAverage );
    }

    public short ToInt16( IFormatProvider provider )
    {
        return Convert.ToInt16( CalcNLimitAverage( 
            Int16.MinValue, Int16.MaxValue, provider ) );
    }

    public int ToInt32( IFormatProvider provider )
    {
        return Convert.ToInt32( CalcNLimitAverage( 
            Int32.MinValue, Int32.MaxValue, provider ) );
    }

    public long ToInt64( IFormatProvider provider )
    {
        // The Double conversion rounds Int64.MinValue and 
        // Int64.MaxValue to invalid Int64 values, so the following 
        // limits must be used.
        return Convert.ToInt64( CalcNLimitAverage( 
            -9223372036854775000, 9223372036854775000, provider ) );
    }

    public SByte ToSByte( IFormatProvider provider )
    {
        return Convert.ToSByte( CalcNLimitAverage( 
            SByte.MinValue, SByte.MaxValue, provider ) );
    }

    public float ToSingle( IFormatProvider provider )
    {
        return Convert.ToSingle( CalcNLimitAverage( 
            Single.MinValue, Single.MaxValue, provider ) );
    }

    public UInt16 ToUInt16( IFormatProvider provider )
    {
        return Convert.ToUInt16( CalcNLimitAverage( 
            UInt16.MinValue, UInt16.MaxValue, provider ) );
    }

    public UInt32 ToUInt32( IFormatProvider provider )
    {
        return Convert.ToUInt32( CalcNLimitAverage( 
            UInt32.MinValue, UInt32.MaxValue, provider ) );
    }

    public UInt64 ToUInt64( IFormatProvider provider )
    {
        // The Double conversion rounds UInt64.MaxValue to an invalid
        // UInt64 value, so the following limit must be used.
        return Convert.ToUInt64( CalcNLimitAverage( 
            0, 18446744073709550000.0, provider ) );
    }

    public object ToType( Type conversionType, 
        IFormatProvider provider )
    {
        return Convert.ChangeType( Average( 
            GetAverageInfo( provider ).TypeOfAverage ), 
            conversionType );
    }

    public string ToString( IFormatProvider provider )
    {
        AverageType avgType = GetAverageInfo( provider ).TypeOfAverage;
        return String.Format( "( {0}: {1:G10} )", avgType, 
            Average( avgType ) );
    }
}
   
class IConvertibleProviderDemo
{
    // Display a DataSet with three different format providers.
    public static void DisplayDataSet( DataSet ds )
    {
        string      fmt    = "{0,-12}{1,20}{2,20}{3,20}";
        AverageInfo median = new AverageInfo( AverageType.Median );
        AverageInfo geMean = 
            new AverageInfo( AverageType.GeometricMean );

         // Display the dataset elements.
        if( ds.Count > 0 )
        {
            Console.Write( "\nDataSet: [{0}", ds[ 0 ] );
            for( int iX = 1; iX < ds.Count; iX++ )
                Console.Write( ", {0}", ds[ iX ] );
            Console.WriteLine( "]\n" );
        }

        Console.WriteLine( fmt, "Convert.", "Default", 
            "Geometric Mean", "Median");
        Console.WriteLine( fmt, "--------", "-------", 
            "--------------", "------");
        Console.WriteLine( fmt, "ToBoolean", 
            Convert.ToBoolean( ds, null ), 
            Convert.ToBoolean( ds, geMean ), 
            Convert.ToBoolean( ds, median ) );
        Console.WriteLine( fmt, "ToByte", 
            Convert.ToByte( ds, null ), 
            Convert.ToByte( ds, geMean ), 
            Convert.ToByte( ds, median ) );
        Console.WriteLine( fmt, "ToChar", 
            Convert.ToChar( ds, null ), 
            Convert.ToChar( ds, geMean ), 
            Convert.ToChar( ds, median ) );
        Console.WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}" +
            "{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}", 
            "ToDateTime", Convert.ToDateTime( ds, null ), 
            Convert.ToDateTime( ds, geMean ), 
            Convert.ToDateTime( ds, median ) );
        Console.WriteLine( fmt, "ToDecimal", 
            Convert.ToDecimal( ds, null ), 
            Convert.ToDecimal( ds, geMean ), 
            Convert.ToDecimal( ds, median ) );
        Console.WriteLine( fmt, "ToDouble", 
            Convert.ToDouble( ds, null ), 
            Convert.ToDouble( ds, geMean ), 
            Convert.ToDouble( ds, median ) );
        Console.WriteLine( fmt, "ToInt16", 
            Convert.ToInt16( ds, null ), 
            Convert.ToInt16( ds, geMean ), 
            Convert.ToInt16( ds, median ) );
        Console.WriteLine( fmt, "ToInt32", 
            Convert.ToInt32( ds, null ), 
            Convert.ToInt32( ds, geMean ), 
            Convert.ToInt32( ds, median ) );
        Console.WriteLine( fmt, "ToInt64", 
            Convert.ToInt64( ds, null ), 
            Convert.ToInt64( ds, geMean ), 
            Convert.ToInt64( ds, median ) );
        Console.WriteLine( fmt, "ToSByte", 
            Convert.ToSByte( ds, null ), 
            Convert.ToSByte( ds, geMean ), 
            Convert.ToSByte( ds, median ) );
        Console.WriteLine( fmt, "ToSingle", 
            Convert.ToSingle( ds, null ), 
            Convert.ToSingle( ds, geMean ), 
            Convert.ToSingle( ds, median ) );
        Console.WriteLine( fmt, "ToUInt16", 
            Convert.ToUInt16( ds, null ), 
            Convert.ToUInt16( ds, geMean ), 
            Convert.ToUInt16( ds, median ) );
        Console.WriteLine( fmt, "ToUInt32", 
            Convert.ToUInt32( ds, null ), 
            Convert.ToUInt32( ds, geMean ), 
            Convert.ToUInt32( ds, median ) );
        Console.WriteLine( fmt, "ToUInt64", 
            Convert.ToUInt64( ds, null ), 
            Convert.ToUInt64( ds, geMean ), 
            Convert.ToUInt64( ds, median ) );
    }
   
    public static void Main( )
    {
        Console.WriteLine( "This example of " +
            "the Convert.To<Type>( object, IFormatProvider ) methods " +
            "\ngenerates the following output. The example " +
            "displays the values \nreturned by the methods, " +
            "using several IFormatProvider objects.\n" );
          
        DataSet ds1 = new DataSet( 
            10.5, 22.2, 45.9, 88.7, 156.05, 297.6 );
        DisplayDataSet( ds1 );
          
        DataSet ds2 = new DataSet( 
            359999.95, 425000, 499999.5, 775000, 1695000 );
        DisplayDataSet( ds2 );
    }
}

/*
This example of the Convert.To<Type>( object, IFormatProvider ) methods
generates the following output. The example displays the values
returned by the methods, using several IFormatProvider objects.

DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]

Convert.                 Default      Geometric Mean              Median
--------                 -------      --------------              ------
ToBoolean                   True                True                True
ToByte                       103                  59                  67
ToChar                         g                   ;                   C
ToDateTime   2003-05-13 15:04:12 2003-05-13 15:03:28 2003-05-13 15:03:35
ToDecimal       103.491666666667    59.4332135445164                67.3
ToDouble        103.491666666667    59.4332135445164                67.3
ToInt16                      103                  59                  67
ToInt32                      103                  59                  67
ToInt64                      103                  59                  67
ToSByte                      103                  59                  67
ToSingle                103.4917            59.43321                67.3
ToUInt16                     103                  59                  67
ToUInt32                     103                  59                  67
ToUInt64                     103                  59                  67

DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]

Convert.                 Default      Geometric Mean              Median
--------                 -------      --------------              ------
ToBoolean                   True                True                True
ToByte                       255                 255                 255
ToChar                         ?                   ?                   ?
ToDateTime   2003-05-22 07:39:08 2003-05-20 22:28:45 2003-05-19 09:55:48
ToDecimal              750999.89    631577.237188435            499999.5
ToDouble               750999.89    631577.237188435            499999.5
ToInt16                    32767               32767               32767
ToInt32                   751000              631577              500000
ToInt64                   751000              631577              500000
ToSByte                      127                 127                 127
ToSingle                750999.9            631577.3            499999.5
ToUInt16                   65535               65535               65535
ToUInt32                  751000              631577              500000
ToUInt64                  751000              631577              500000
*/
Imports System.Collections

Module IConvertibleProviderDemo

    ' Define the types of averaging available in the class 
    ' implementing IConvertible.
    Enum AverageType as Short
        None = 0
        GeometricMean = 1
        ArithmeticMean = 2
        Median = 3
    End Enum

    ' Pass an instance of this class to methods that require an 
    ' IFormatProvider. The class instance determines the type of 
    ' average to calculate.
    Public Class AverageInfo
        Implements IFormatProvider

        Protected  AvgType      As AverageType

        ' Specify the type of averaging in the constructor.
        Public Sub New( avgType As AverageType )
            Me.AvgType = avgType
        End Sub

        ' This method returns a reference to the containing object 
        ' if an object of AverageInfo type is requested. 
        Public Function GetFormat( argType As Type ) As Object _
            Implements IFormatProvider.GetFormat

            If argType Is GetType( AverageInfo ) Then
                Return Me
            Else
                Return Nothing
            End If
        End Function 

        ' Use this property to set or get the type of averaging.
        Public Property TypeOfAverage( ) As AverageType
            Get
                Return Me.AvgType
            End Get
            Set( ByVal value as AverageType )
                Me.AvgType = value
            End Set
        End Property
    End Class 

    ' This class encapsulates an array of Double values and implements 
    ' the IConvertible interface. Most of the IConvertible methods 
    ' return an average of the array elements in one of three types: 
    ' arithmetic mean, geometric mean, or median. 
    Public Class DataSet
        Implements IConvertible

        Protected data              As ArrayList
        Protected defaultProvider   As AverageInfo
           
        ' Construct the object and add an initial list of values.
        ' Create a default format provider.
        Public Sub New( ParamArray values( ) As Double )
            data = New ArrayList( values )
            defaultProvider = New AverageInfo( _
                AverageType.ArithmeticMean )  
        End Sub
           
        ' Add additional values with this method.
        Public Function Add( value As Double ) As Integer
            data.Add( value )
            Return data.Count
        End Function
           
        ' Get, set, and add values with this indexer property.
        Default Public Property Item(index As Integer) As Double
            Get
                If index >= 0 AndAlso index < data.Count Then
                    Return System.Convert.ToDouble( data( index ) )
                Else
                    Throw New InvalidOperationException( _
                        "[DataSet.get] Index out of range." )
                End If
            End Get
            Set
                If index >= 0 AndAlso index < data.Count Then
                    data( index ) = value
                 
                ElseIf index = data.Count Then
                    data.Add( value )
                Else
                    Throw New InvalidOperationException( _
                        "[DataSet.set] Index out of range." )
                End If
            End Set
        End Property
          
        ' This property returns the number of elements in the object.
        Public ReadOnly Property Count( ) As Integer
            Get
                Return data.Count
            End Get
        End Property

        ' This method calculates the average of the object's elements.
        Protected Function Average( ByVal avgType As AverageType ) As Double

            Dim SumProd As Double 
            Dim Index   As Integer

            If data.Count = 0 Then Return 0.0

            Select Case avgType
                
                Case AverageType.GeometricMean

                    SumProd = 1.0
                    For Index = 0 To data.Count - 1
                        SumProd *= data( Index )
                    Next Index
                    
                    ' This calculation will not fail with negative 
                    ' elements.
                    Return Math.Sign( SumProd ) * Math.Pow( _
                        Math.Abs( SumProd ), 1.0 / data.Count )

                Case AverageType.ArithmeticMean

                    SumProd = 0.0
                    For Index = 0 To data.Count - 1
                        SumProd += data( Index )
                    Next Index

                    Return SumProd / data.Count 

                Case AverageType.Median

                    If data.Count Mod 2 = 0 Then
                        Return ( data( data.Count \ 2 ) + _
                            data( data.Count \ 2 - 1 ) ) / 2.0
                    Else
                        Return data( data.Count \ 2 ) 
                    End If
            End Select
        End Function

        ' Get the AverageInfo object from the caller's format 
        ' provider, or use the local default.
        Protected Function GetAverageInfo( _
            provider As IFormatProvider ) As AverageInfo

            Dim avgInfo As AverageInfo = Nothing

            If Not provider Is Nothing Then
                avgInfo = provider.GetFormat( GetType( AverageInfo ) )
            End If

            Return IIf( avgInfo Is Nothing, defaultProvider, avgInfo )
            
        End Function           

        ' Calculate the average and limit the range.
        Protected Function CalcNLimitAverage( min As Double, _
            max As Double, provider as IFormatProvider ) As Double

            ' Get the format provider and calculate the average.
            Dim avgInfo As AverageInfo = GetAverageInfo( provider )
            Dim avg As Double = Average( avgInfo.TypeOfAverage )

            ' Limit the range, based on the minimum and maximum values 
            ' for the type.
            Return IIf( avg > max, max, IIf( avg < min, min, avg ) )

        End Function

        ' The following elements are required by IConvertible.

        ' None of these conversion functions throw exceptions. When
        ' the data is out of range for the type, the appropriate
        ' MinValue or MaxValue is used.
        Public Function GetTypeCode( ) As TypeCode _
            Implements IConvertible.GetTypeCode
            Return TypeCode.Object
        End Function

        Function ToBoolean( ByVal provider As IFormatProvider ) As _
            Boolean Implements IConvertible.ToBoolean

            ' ToBoolean is false if the dataset is empty.
            If data.Count <= 0 Then
                Return False

            ' For median averaging, ToBoolean is true if any 
            ' non-discarded elements are nonzero.
            ElseIf AverageType.Median = _
                GetAverageInfo( provider ).TypeOfAverage Then

                If data.Count Mod 2 = 0 Then
                    Return ( data( data.Count \ 2 ) <> 0.0 Or _
                        data( data.Count \ 2 - 1 ) <> 0.0 )
                Else
                    Return data( data.Count \ 2 ) <> 0.0
                End If

            ' For arithmetic or geometric mean averaging, ToBoolean is 
            ' true if any element of the dataset is nonzero.  
            Else
                Dim Index As Integer
                For Index = 0 To data.Count - 1
                    If data( Index ) <> 0.0 Then Return True
                Next Index
                Return False
            End If
        End Function

        Function ToByte( ByVal provider As IFormatProvider ) As Byte _
            Implements IConvertible.ToByte
            Return Convert.ToByte( CalcNLimitAverage( _
                Byte.MinValue, Byte.MaxValue, provider ) )
        End Function

        Function ToChar( ByVal provider As IFormatProvider ) As Char _
            Implements IConvertible.ToChar
            Return Convert.ToChar( Convert.ToUInt16( _
                CalcNLimitAverage( 0.0, &HFFFF, provider ) ) )
        End Function

        ' Convert to DateTime by adding the calculated average as 
        ' seconds to the current date and time. A valid DateTime is 
        ' always returned.
        Function ToDateTime( ByVal provider As IFormatProvider ) As _
            DateTime Implements IConvertible.ToDateTime
            Dim seconds As Double = Average( _
                GetAverageInfo( provider ).TypeOfAverage )
            Try
                Return DateTime.Now.AddSeconds( seconds )
            Catch ex As ArgumentOutOfRangeException 
                Return IIf( seconds < 0.0, DateTime.MinValue, _
                    DateTime.MaxValue )
            End Try
        End Function

        Function ToDecimal( ByVal provider As IFormatProvider ) As _
            Decimal Implements IConvertible.ToDecimal

            ' The Double conversion rounds Decimal.MinValue and
            ' Decimal.MaxValue to invalid Decimal values, so the 
            ' following limits must be used.
            Return Convert.ToDecimal( CalcNLimitAverage( _
                -79228162514264330000000000000.0, _
                79228162514264330000000000000.0, provider ) )
        End Function

        Function ToDouble( ByVal provider As IFormatProvider) As _
            Double Implements IConvertible.ToDouble
            Return Average( GetAverageInfo( provider ).TypeOfAverage )
        End Function

        Function ToInt16( ByVal provider As IFormatProvider ) As _
            Short Implements IConvertible.ToInt16
            Return Convert.ToInt16( CalcNLimitAverage( _
                Int16.MinValue, Int16.MaxValue, provider ) )
        End Function

        Function ToInt32( ByVal provider As IFormatProvider ) As _
            Integer Implements IConvertible.ToInt32
            Return Convert.ToInt32( CalcNLimitAverage( _
                Int32.MinValue, Int32.MaxValue, provider ) )
        End Function

        Function ToInt64( ByVal provider As IFormatProvider ) As Long _
            Implements IConvertible.ToInt64

            ' The Double conversion rounds Int64.MinValue and 
            ' Int64.MaxValue to invalid Long values, so the following 
            ' limits must be used.
            Return Convert.ToInt64( CalcNLimitAverage( _
                -9223372036854775000, 9223372036854775000, provider ) )
        End Function

        Function ToSByte( ByVal provider As IFormatProvider ) As _
            SByte Implements IConvertible.ToSByte

            ' SByte.MinValue and SByte.MaxValue are not defined in
            ' Visual Basic.
            Return Convert.ToSByte( CalcNLimitAverage( _
                -128, 127, provider ) )
        End Function

        Function ToSingle( ByVal provider As IFormatProvider ) As _
            Single Implements IConvertible.ToSingle
            Return Convert.ToSingle( CalcNLimitAverage( _
                Single.MinValue, Single.MaxValue, provider ) )
        End Function

        Function ToUInt16( ByVal provider As IFormatProvider ) As _
            UInt16 Implements IConvertible.ToUInt16

            ' UInt16.MinValue and UInt16.MaxValue are not defined in 
            ' Visual Basic.
            Return Convert.ToUInt16( CalcNLimitAverage( _
                0, &HFFFF, provider ) )
        End Function

        Function ToUInt32( ByVal provider As IFormatProvider ) As _
            UInt32 Implements IConvertible.ToUInt32

            ' UInt32.MinValue and UInt32.MaxValue are not defined in 
            ' Visual Basic.
            Return Convert.ToUInt32( CalcNLimitAverage( _
                0, 4294967295, provider ) )
        End Function

        Function ToUInt64( ByVal provider As IFormatProvider ) As _
            UInt64 Implements IConvertible.ToUInt64

            ' UInt64.MinValue and UInt64.MaxValue are not defined in 
            ' Visual Basic. The Double conversion would have rounded 
            ' UInt64.MaxValue, so the following limit must be used.
            Return Convert.ToUInt64( CalcNLimitAverage( _
                0, 18446744073709550000.0, provider ) )
        End Function

        Function ToType( ByVal conversionType As Type, _
            ByVal provider As IFormatProvider) As Object _
            Implements IConvertible.ToType
            Return Convert.ChangeType( Average( GetAverageInfo( _
                provider ).TypeOfAverage ), conversionType )
        End Function

        Overloads Function ToString( ByVal provider As IFormatProvider _
            ) As String Implements IConvertible.ToString
            Dim avgType as AverageType = _
                GetAverageInfo( provider ).TypeOfAverage
            Return String.Format( "( {0}: {1:G10} )", avgType, _
                Average( avgType ) )
        End Function
    End Class
   
    ' Display a DataSet with three different format providers.
    Sub DisplayDataSet( ds As DataSet )

        Dim fmt    As String      = "{0,-12}{1,20}{2,20}{3,20}"
        Dim median As AverageInfo = New AverageInfo( AverageType.Median )
        Dim geMean As AverageInfo = _
            New AverageInfo( AverageType.GeometricMean )
        Dim iX     As Integer

        ' Display the dataset elements.
        If ds.Count > 0 Then
            Console.Write( vbCrLf & "DataSet: [{0}", ds( 0 ) )
            For iX = 1 To ds.Count - 1
                Console.Write( ", {0}", ds( iX ) )
            Next iX
            Console.WriteLine( "]" & vbCrLf )
        End If

        Console.WriteLine( fmt, "Convert.", "Default", _
            "Geometric Mean", "Median" )
        Console.WriteLine( fmt, "--------", "-------", _
            "--------------", "------" )
        Console.WriteLine( fmt, "ToBoolean", _
            Convert.ToBoolean( ds, Nothing ), _
            Convert.ToBoolean( ds, geMean ), _
            Convert.ToBoolean( ds, median ) )
        Console.WriteLine( fmt, "ToByte", _
            Convert.ToByte( ds, Nothing ), _
            Convert.ToByte( ds, geMean ), _
            Convert.ToByte( ds, median ) )
        Console.WriteLine( fmt, "ToChar", _
            Convert.ToChar( ds, Nothing ), _
            Convert.ToChar( ds, geMean ), _
            Convert.ToChar( ds, median ) )
        Console.WriteLine( "{0,-12}{1,20:yyyy-MM-dd HH:mm:ss}" & _
            "{2,20:yyyy-MM-dd HH:mm:ss}{3,20:yyyy-MM-dd HH:mm:ss}", _
            "ToDateTime", Convert.ToDateTime( ds, Nothing ), _
            Convert.ToDateTime( ds, geMean ), _
            Convert.ToDateTime( ds, median ) )
        Console.WriteLine( fmt, "ToDecimal", _
            Convert.ToDecimal( ds, Nothing ), _
            Convert.ToDecimal( ds, geMean ), _
            Convert.ToDecimal( ds, median ) )
        Console.WriteLine( fmt, "ToDouble", _
            Convert.ToDouble( ds, Nothing ), _
            Convert.ToDouble( ds, geMean ), _
            Convert.ToDouble( ds, median ) )
        Console.WriteLine( fmt, "ToInt16", _
            Convert.ToInt16( ds, Nothing ), _
            Convert.ToInt16( ds, geMean ), _
            Convert.ToInt16( ds, median ) )
        Console.WriteLine( fmt, "ToInt32", _
            Convert.ToInt32( ds, Nothing ), _
            Convert.ToInt32( ds, geMean ), _
            Convert.ToInt32( ds, median ) )
        Console.WriteLine( fmt, "ToInt64", _
            Convert.ToInt64( ds, Nothing ), _
            Convert.ToInt64( ds, geMean ), _
            Convert.ToInt64( ds, median ) )
        Console.WriteLine( fmt, "ToSByte", _
            Convert.ToSByte( ds, Nothing ), _
            Convert.ToSByte( ds, geMean ), _
            Convert.ToSByte( ds, median ) )
        Console.WriteLine( fmt, "ToSingle", _
            Convert.ToSingle( ds, Nothing ), _
            Convert.ToSingle( ds, geMean ), _
            Convert.ToSingle( ds, median ) )
        Console.WriteLine( fmt, "ToUInt16", _
            Convert.ToUInt16( ds, Nothing ), _
            Convert.ToUInt16( ds, geMean ), _
            Convert.ToUInt16( ds, median ) )
        Console.WriteLine( fmt, "ToUInt32", _
            Convert.ToUInt32( ds, Nothing ), _
            Convert.ToUInt32( ds, geMean ), _
            Convert.ToUInt32( ds, median ) )
        Console.WriteLine( fmt, "ToUInt64", _
            Convert.ToUInt64( ds, Nothing ), _
            Convert.ToUInt64( ds, geMean ), _
            Convert.ToUInt64( ds, median ) )
    End Sub
   
    Sub Main( )
        Console.WriteLine( _
            "This example of the Convert.To<Type>( Object, " & _
            "IFormatProvider ) methods " & vbCrLf & "generates " & _
            "the following output. The example displays the " & _
            "values " & vbCrLf & "returned by the methods, " & _
            "using several IFormatProvider objects." & vbCrLf )
          
        Dim ds1 As New DataSet( 10.5, 22.2, 45.9, 88.7, 156.05, 297.6 )
        DisplayDataSet( ds1 )
          
        Dim ds2 As New DataSet( _
            359999.95, 425000, 499999.5, 775000, 1695000 )
        DisplayDataSet( ds2 )
    End Sub 
End Module 

' This example of the Convert.To<Type>( Object, IFormatProvider ) methods
' generates the following output. The example displays the values
' returned by the methods, using several IFormatProvider objects.
' 
' DataSet: [10.5, 22.2, 45.9, 88.7, 156.05, 297.6]
' 
' Convert.                 Default      Geometric Mean              Median
' --------                 -------      --------------              ------
' ToBoolean                   True                True                True
' ToByte                       103                  59                  67
' ToChar                         g                   ;                   C
' ToDateTime   2003-05-13 14:52:53 2003-05-13 14:52:09 2003-05-13 14:52:17
' ToDecimal       103.491666666667    59.4332135445164                67.3
' ToDouble        103.491666666667    59.4332135445164                67.3
' ToInt16                      103                  59                  67
' ToInt32                      103                  59                  67
' ToInt64                      103                  59                  67
' ToSByte                      103                  59                  67
' ToSingle                103.4917            59.43321                67.3
' ToUInt16                     103                  59                  67
' ToUInt32                     103                  59                  67
' ToUInt64                     103                  59                  67
' 
' DataSet: [359999.95, 425000, 499999.5, 775000, 1695000]
' 
' Convert.                 Default      Geometric Mean              Median
' --------                 -------      --------------              ------
' ToBoolean                   True                True                True
' ToByte                       255                 255                 255
' ToChar                         ?                   ?                   ?
' ToDateTime   2003-05-22 07:27:49 2003-05-20 22:17:27 2003-05-19 09:44:29
' ToDecimal              750999.89    631577.237188435            499999.5
' ToDouble               750999.89    631577.237188435            499999.5
' ToInt16                    32767               32767               32767
' ToInt32                   751000              631577              500000
' ToInt64                   751000              631577              500000
' ToSByte                      127                 127                 127
' ToSingle                750999.9            631577.3            499999.5
' ToUInt16                   65535               65535               65535
' ToUInt32                  751000              631577              500000
' ToUInt64                  751000              631577              500000

Commenti

Il valore restituito è il risultato ottenuto richiamando la IConvertible.ToInt32 metodo del tipo sottostante di value.The return value is the result of invoking the IConvertible.ToInt32 method of the underlying type of value.

provider consente all'utente di specificare le informazioni specifiche delle impostazioni cultura conversione sul contenuto di value.provider enables the user to specify culture-specific conversion information about the contents of value. Ad esempio, se value è un String che rappresenta un numero, provider potrebbe fornire informazioni specifiche delle impostazioni cultura sulla notazione usata per rappresentare il numero.For example, if value is a String that represents a number, provider could supply culture-specific information about the notation used to represent that number.

Ignorano i tipi di base provider; tuttavia, il parametro può essere utilizzato se value è un tipo definito dall'utente che implementa il IConvertible interfaccia.The base types ignore provider; however, the parameter may be used if value is a user-defined type that implements the IConvertible interface.

ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider) ToInt32(String, IFormatProvider)

Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 32 bit equivalente mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the specified string representation of a number to an equivalent 32-bit signed integer, using the specified culture-specific formatting information.

public:
 static int ToInt32(System::String ^ value, IFormatProvider ^ provider);
public static int ToInt32 (string value, IFormatProvider provider);
static member ToInt32 : string * IFormatProvider -> int
Public Shared Function ToInt32 (value As String, provider As IFormatProvider) As Integer

Parametri

value
String String String String

Stringa che contiene il numero da convertire.A string that contains the number to convert.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

Oggetto che fornisce informazioni di formattazione specifiche delle impostazioni cultura.An object that supplies culture-specific formatting information.

Restituisce

Intero con segno a 32 bit equivalente al numero in value oppure 0 (zero) se value è null.A 32-bit signed integer that is equivalent to the number in value, or 0 (zero) if value is null.

Eccezioni

value non è costituito da un segno facoltativo seguito da una sequenza di cifre (da 0 a 9).value does not consist of an optional sign followed by a sequence of digits (0 through 9).

L'oggetto value rappresenta un numero minore di MinValue o maggiore di MaxValue.value represents a number that is less than MinValue or greater than MaxValue.

Esempi

L'esempio seguente definisce una classe personalizzata NumberFormatInfo che riconosce la stringa "pos" come segno positivo e la stringa "neg" come il segno negativo.The following example defines a custom NumberFormatInfo object that recognizes the string "pos" as the positive sign and the string "neg" as the negative sign. Tenta di convertire ogni elemento della matrice di stringhe numeriche in un intero utilizzando questo provider di entrambi e NumberFormatInfo provider per le impostazioni cultura invarianti.It then attempts to convert each element of a numeric string array to an integer using both this provider and the NumberFormatInfo provider for the invariant culture.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      // Create a custom NumberFormatInfo object and set its two properties
      // used by default in parsing numeric strings.
      NumberFormatInfo customProvider = new NumberFormatInfo();
      customProvider.NegativeSign = "neg ";
      customProvider.PositiveSign = "pos ";

      // Add custom and invariant provider to an array of providers.
      NumberFormatInfo[] providers = { customProvider, NumberFormatInfo.InvariantInfo };
      
      // Define an array of strings to convert.
      string[] numericStrings = { "123456789", "+123456789", "pos 123456789",
                                  "-123456789", "neg 123456789", "123456789.",
                                  "123,456,789", "(123456789)", "2147483648",
                                  "-2147483649" }; 
      
      // Use each provider to parse all the numeric strings.
      for (int ctr = 0; ctr <= 1; ctr++)
      {
         IFormatProvider provider = providers[ctr];
         Console.WriteLine(ctr == 0 ? "Custom Provider:" : "Invariant Provider:");
         foreach (string numericString in numericStrings)
         {
            Console.Write("{0,15}  --> ", numericString);
            try {
               Console.WriteLine("{0,20}", Convert.ToInt32(numericString, provider));
            }
            catch (FormatException) {
               Console.WriteLine("{0,20}", "FormatException");
            }    
            catch (OverflowException) {
               Console.WriteLine("{0,20}", "OverflowException");                 
            }
         }
         Console.WriteLine();
      }                  
   }
}
// The example displays the following output:
//       Custom Provider:
//             123456789  -->            123456789
//            +123456789  -->      FormatException
//         pos 123456789  -->            123456789
//            -123456789  -->      FormatException
//         neg 123456789  -->           -123456789
//            123456789.  -->      FormatException
//           123,456,789  -->      FormatException
//           (123456789)  -->      FormatException
//            2147483648  -->    OverflowException
//           -2147483649  -->      FormatException
//       
//       Invariant Provider:
//             123456789  -->            123456789
//            +123456789  -->            123456789
//         pos 123456789  -->      FormatException
//            -123456789  -->           -123456789
//         neg 123456789  -->      FormatException
//            123456789.  -->      FormatException
//           123,456,789  -->      FormatException
//           (123456789)  -->      FormatException
//            2147483648  -->    OverflowException
//           -2147483649  -->    OverflowException
Imports System.Globalization

Module Example
   Public Sub Main()
      ' Create a custom NumberFormatInfo object and set its two properties
      ' used by default in parsing numeric strings.
      Dim customProvider As New NumberFormatInfo()
      customProvider.NegativeSign = "neg "
      customProvider.PositiveSign = "pos "

      ' Add custom and invariant provider to an array of providers.
      Dim providers() As NumberFormatInfo = { customProvider, NumberFormatInfo.InvariantInfo }
      
      ' Define an array of strings to convert.
      Dim numericStrings() As String = { "123456789", "+123456789", "pos 123456789", _
                                         "-123456789", "neg 123456789", "123456789.", _
                                         "123,456,789", "(123456789)", "2147483648", _
                                         "-2147483649" } 
      
      ' Use each provider to parse all the numeric strings.
      For ctr As Integer = 0 To 1
         Dim provider As IFormatPRovider = providers(ctr)
         Console.WriteLine(IIf(ctr = 0, "Custom Provider:", "Invariant Provider:"))
         For Each numericString As String In numericStrings
            Console.Write("{0,15}  --> ", numericString)
            Try
               Console.WriteLine("{0,20}", Convert.ToInt32(numericString, provider))
            Catch e As FormatException
               Console.WriteLine("{0,20}", "FormatException") 
            Catch e As OverflowException
               Console.WriteLine("{0,20}", "OverflowException")                 
            End Try
         Next
         Console.WriteLine()
      Next                  
   End Sub 
End Module 
' The example displays the following output:
'       Custom Provider:
'             123456789  -->            123456789
'            +123456789  -->      FormatException
'         pos 123456789  -->            123456789
'            -123456789  -->      FormatException
'         neg 123456789  -->           -123456789
'            123456789.  -->      FormatException
'           123,456,789  -->      FormatException
'           (123456789)  -->      FormatException
'            2147483648  -->    OverflowException
'           -2147483649  -->      FormatException
'       
'       Invariant Provider:
'             123456789  -->            123456789
'            +123456789  -->            123456789
'         pos 123456789  -->      FormatException
'            -123456789  -->           -123456789
'         neg 123456789  -->      FormatException
'            123456789.  -->      FormatException
'           123,456,789  -->      FormatException
'           (123456789)  -->      FormatException
'            2147483648  -->    OverflowException
'           -2147483649  -->    OverflowException

Commenti

Il valore restituito è il risultato ottenuto richiamando la Int32.Parse metodo value.The return value is the result of invoking the Int32.Parse method on value.

provider è un' IFormatProvider istanza che consente di ottenere un NumberFormatInfo oggetto.provider is an IFormatProvider instance that obtains a NumberFormatInfo object. Il NumberFormatInfo oggetto fornisce informazioni specifiche delle impostazioni cultura relative al formato di value.The NumberFormatInfo object provides culture-specific information about the format of value. Se provider viene null, il NumberFormatInfo per la lingua corrente viene utilizzata.If provider is null, the NumberFormatInfo for the current culture is used.

Se si preferisce non gestire un'eccezione se la conversione non riesce, è possibile chiamare il Int32.TryParse metodo invece.If you prefer not to handle an exception if the conversion fails, you can call the Int32.TryParse method instead. Restituisce un Boolean valore che indica se la conversione ha avuto esito positivo o negativo.It returns a Boolean value that indicates whether the conversion succeeded or failed.

ToInt32(String, Int32) ToInt32(String, Int32) ToInt32(String, Int32) ToInt32(String, Int32)

Converte la rappresentazione di stringa di un numero in una base specificata nell'intero con segno a 32 bit equivalente.Converts the string representation of a number in a specified base to an equivalent 32-bit signed integer.

public:
 static int ToInt32(System::String ^ value, int fromBase);
public static int ToInt32 (string value, int fromBase);
static member ToInt32 : string * int -> int
Public Shared Function ToInt32 (value As String, fromBase As Integer) As Integer

Parametri

value
String String String String

Stringa che contiene il numero da convertire.A string that contains the number to convert.

fromBase
Int32 Int32 Int32 Int32

Base del numero in value, che deve essere 2, 8, 10 o 16.The base of the number in value, which must be 2, 8, 10, or 16.

Restituisce

Intero con segno a 32 bit equivalente al numero in value oppure 0 (zero) se value è null.A 32-bit signed integer that is equivalent to the number in value, or 0 (zero) if value is null.

Eccezioni

Il valore di fromBase non è 2, 8, 10 o 16.fromBase is not 2, 8, 10, or 16.

In alternativa-or- value, che rappresenta un numero con segno non in base 10, è preceduto da un segno negativo.value, which represents a non-base 10 signed number, is prefixed with a negative sign.

value contiene un carattere che corrisponde a una cifra non valida nella base specificata da fromBase.value contains a character that is not a valid digit in the base specified by fromBase. Il messaggio di eccezione indica che non ci sono cifre da convertire se il primo carattere in value non è valido; in caso contrario, il messaggio indica che value contiene caratteri finali non validi.The exception message indicates that there are no digits to convert if the first character in value is invalid; otherwise, the message indicates that value contains invalid trailing characters.

value, che rappresenta un numero con segno non in base 10, è preceduto da un segno negativo.value, which represents a non-base 10 signed number, is prefixed with a negative sign.

In alternativa-or- L'oggetto value rappresenta un numero minore di MinValue o maggiore di MaxValue.value represents a number that is less than MinValue or greater than MaxValue.

Commenti

Se fromBase è 16, è possibile anteporre al numero specificato da di value parametro con "0x" o "0x".If fromBase is 16, you can prefix the number specified by the value parameter with "0x" or "0X".

Poiché il segno negativo non è supportato per la rappresentazione numerica non in base 10, il ToInt32(String, Int32) metodo presuppone che i numeri negativi per la rappresentazione di complemento a uno di due.Because the negative sign is not supported for non-base 10 numeric representations, the ToInt32(String, Int32) method assumes that negative numbers use two's complement representation. In altre parole, il metodo sempre interpreta i bit più significativo binario di un numero intero (31 bit) come bit di segno.In other words, the method always interprets the highest-order binary bit of an integer (bit 31) as its sign bit. Di conseguenza, è possibile scrivere codice in cui una non in base 10 numeri che è compreso nell'intervallo del Int32 tipo di dati viene convertito in un Int32 valore senza il metodo che genera un'eccezione.As a result, it is possible to write code in which a non-base 10 number that is out of the range of the Int32 data type is converted to an Int32 value without the method throwing an exception. Gli incrementi di esempio seguenti Int32.MaxValue di uno, converte il numero risulta nella relativa rappresentazione di stringa esadecimale e quindi chiama il ToInt32(String, Int32) (metodo).The following example increments Int32.MaxValue by one, converts the resulting number to its hexadecimal string representation, and then calls the ToInt32(String, Int32) method. Anziché generare un'eccezione, il metodo visualizza il messaggio "0x80000000 viene convertito in tra -2147483648".Instead of throwing an exception, the method displays the message, "0x80000000 converts to -2147483648."

// Create a hexadecimal value out of range of the integer type. 
String^ value1 = Convert::ToString((static_cast<__int64>(int::MaxValue)) + 1, 16);
// Convert it back to a number.
try {
   int number = Convert::ToInt32(value1, 16);
   Console::WriteLine("0x{0} converts to {1}.", value1, number);
}
catch (OverflowException ^e) {
   Console::WriteLine("Unable to convert '0x{0}' to an integer.", value1);
}
// The example displays the following output:
//      0x80000000 converts to -2147483648.
// Create a hexadecimal value out of range of the Integer type.
string value = Convert.ToString((long) int.MaxValue + 1, 16);
// Convert it back to a number.
try
{
   int number = Convert.ToInt32(value, 16);
   Console.WriteLine("0x{0} converts to {1}.", value, number.ToString());
}
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to an integer.", value);
}   
' Create a hexadecimal value out of range of the Integer type.
Dim value As String = Convert.ToString(CLng(Integer.MaxValue) + 1, 16)
' Convert it back to a number.
Try
   Dim number As Integer = Convert.ToInt32(value, 16)
   Console.WriteLine("0x{0} converts to {1}.", value, number)
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to an integer.", value)
End Try   

Quando si esegue operazioni binarie o conversioni numeriche, è sempre la responsabilità dello sviluppatore per verificare che un metodo viene utilizzata la rappresentazione numerica appropriata per interpretare un valore specifico.When performing binary operations or numeric conversions, it is always the responsibility of the developer to verify that a method is using the appropriate numeric representation to interpret a particular value. Come illustrato nell'esempio seguente, è possibile garantire che i metodo consente di gestire gli overflow in modo appropriato, recuperando prima il segno del valore numerico prima di convertirlo nella relativa rappresentazione di stringa esadecimale.As the following example illustrates, you can ensure that the method handles overflows appropriately by first retrieving the sign of the numeric value before converting it to its hexadecimal string representation. Generare un'eccezione se il valore originale era positivo, ma la conversione in un intero produce un valore negativo.Throw an exception if the original value was positive but the conversion back to an integer yields a negative value.

__int64 sourceNumber2 = (static_cast<__int64>(int::MaxValue)) + 1;
bool isNegative = Math::Sign(sourceNumber2) == -1;
String^ value2 = Convert::ToString(sourceNumber2, 16);
int targetNumber;
try {
   targetNumber = Convert::ToInt32(value2, 16);
   if (!(isNegative) & (targetNumber & 0x80000000) != 0)
      throw gcnew OverflowException();
   else
      Console::WriteLine("0x{0} converts to {1}.", value2, targetNumber);
}
catch (OverflowException ^e) {
   Console::WriteLine("Unable to convert '0x{0}' to an integer.", value2);
}
// The example displays the following output:
//       Unable to convert '0x80000000' to an integer.
// Create a hexadecimal value out of range of the Integer type.
long sourceNumber = (long) int.MaxValue + 1;
bool isNegative = Math.Sign(sourceNumber) == -1;
string value = Convert.ToString(sourceNumber, 16);
int targetNumber;
try
{
   targetNumber = Convert.ToInt32(value, 16);
   if (!(isNegative) & (targetNumber & 0x80000000) != 0) 
      throw new OverflowException();
   else 
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber);
}
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to an integer.", value);
} 
// Displays the following to the console:
//    Unable to convert '0x80000000' to an integer.    
' Create a hexadecimal value out of range of the Integer type.
Dim sourceNumber As Long = CLng(Integer.MaxValue) + 1
Dim isNegative As Boolean = (Math.Sign(sourceNumber) = -1)
Dim value As String = Convert.ToString(sourceNumber, 16)
Dim targetNumber As Integer
Try
   targetNumber = Convert.ToInt32(value, 16)
   If Not isNegative And ((targetNumber And &H80000000) <> 0) Then
      Throw New OverflowException()
   Else 
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber)
   End If    
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to an integer.", value)
End Try 
' Displays the following to the console:
'    Unable to convert '0x80000000' to an integer.     

ToInt32(UInt64) ToInt32(UInt64) ToInt32(UInt64) ToInt32(UInt64)

Importante

Questa API non è conforme a CLS.

Converte il valore dell'intero senza segno a 64 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 64-bit unsigned integer to an equivalent 32-bit signed integer.

public:
 static int ToInt32(System::UInt64 value);
[System.CLSCompliant(false)]
public static int ToInt32 (ulong value);
static member ToInt32 : uint64 -> int
Public Shared Function ToInt32 (value As ULong) As Integer

Parametri

value
UInt64 UInt64 UInt64 UInt64

Intero senza segno a 64 bit da convertire.The 64-bit unsigned integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Eccezioni

Esempi

Nell'esempio seguente prova a convertire ogni elemento in una matrice di valori unsigned long integer in un intero con segno.The following example attempts to convert each element in an array of unsigned long integers to a signed integer.

ulong[] numbers = { UInt64.MinValue, 121, 340, UInt64.MaxValue };
int result;
foreach (ulong number in numbers)
{
   try {
      result = Convert.ToInt32(number);
      Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    Converted the UInt64 value 0 to a Int32 value 0.
//    Converted the UInt64 value 121 to a Int32 value 121.
//    Converted the UInt64 value 340 to a Int32 value 340.
//    The UInt64 value 18446744073709551615 is outside the range of the Int32 type.
Dim numbers() As ULong = { UInt64.MinValue, 121, 340, UInt64.MaxValue }
Dim result As Integer
For Each number As ULong In numbers
   Try
      result = Convert.ToInt32(number)
      Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    Converted the UInt64 value 0 to a Int32 value 0.
'    Converted the UInt64 value 121 to a Int32 value 121.
'    Converted the UInt64 value 340 to a Int32 value 340.
'    The UInt64 value 18446744073709551615 is outside the range of the Int32 type.

ToInt32(Object) ToInt32(Object) ToInt32(Object) ToInt32(Object)

Converte il valore dell'oggetto specificato in un intero con segno a 32 bit.Converts the value of the specified object to a 32-bit signed integer.

public:
 static int ToInt32(System::Object ^ value);
public static int ToInt32 (object value);
static member ToInt32 : obj -> int
Public Shared Function ToInt32 (value As Object) As Integer

Parametri

value
Object Object Object Object

Oggetto che implementa l'interfaccia IConvertible oppure null.An object that implements the IConvertible interface, or null.

Restituisce

Intero con segno a 32 bit equivalente a value oppure zero se value è null.A 32-bit signed integer equivalent to value, or zero if value is null.

Eccezioni

Il formato di value non è appropriato.value is not in an appropriate format.

value non implementa l'interfaccia IConvertible.value does not implement the IConvertible interface.

In alternativa-or- La conversione non è supportata.The conversion is not supported.

L'oggetto value rappresenta un numero minore di MinValue o maggiore di MaxValue.value represents a number that is less than MinValue or greater than MaxValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento nella matrice di oggetti in un numero intero.The following example attempts to convert each element in an object array to an integer.

object[] values = { true, -12, 163, 935, 'x', new DateTime(2009, 5, 12),
                    "104", "103.0", "-1",
                    "1.00e2", "One", 1.00e2, 16.3e42};
int result;

foreach (object value in values)
{
   try {
      result = Convert.ToInt32(value);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.",
                        value.GetType().Name, value);
   }                     
   catch (FormatException) {
      Console.WriteLine("The {0} value {1} is not in a recognizable format.",
                        value.GetType().Name, value);
   }
   catch (InvalidCastException) {
      Console.WriteLine("No conversion to an Int32 exists for the {0} value {1}.",
                        value.GetType().Name, value);
                        
   }
}                           
// The example displays the following output:
//    Converted the Boolean value True to the Int32 value 1.
//    Converted the Int32 value -12 to the Int32 value -12.
//    Converted the Int32 value 163 to the Int32 value 163.
//    Converted the Int32 value 935 to the Int32 value 935.
//    Converted the Char value x to the Int32 value 120.
//    No conversion to an Int32 exists for the DateTime value 5/12/2009 12:00:00 AM.
//    Converted the String value 104 to the Int32 value 104.
//    The String value 103.0 is not in a recognizable format.
//    Converted the String value -1 to the Int32 value -1.
//    The String value 1.00e2 is not in a recognizable format.
//    The String value One is not in a recognizable format.
//    Converted the Double value 100 to the Int32 value 100.
//    The Double value 1.63E+43 is outside the range of the Int32 type.
Dim values() As Object = { True, -12, 163, 935, "x"c, #5/12/2009#, _
                           "104", "103.0", "-1", _
                           "1.00e2", "One", 1.00e2, 16.3e42}
Dim result As Integer

For Each value As Object In values
   Try
      result = Convert.ToInt32(value)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.", _
                        value.GetType().Name, value)
   Catch e As FormatException
      Console.WriteLine("The {0} value {1} is not in a recognizable format.", _
                        value.GetType().Name, value)
   Catch e As InvalidCastException
      Console.WriteLine("No conversion to an Int32 exists for the {0} value {1}.", _
                        value.GetType().Name, value)
                        
   End Try
Next                           
' The example displays the following output:
'    Converted the Boolean value True to the Int32 value 1.
'    Converted the Int32 value -12 to the Int32 value -12.
'    Converted the Int32 value 163 to the Int32 value 163.
'    Converted the Int32 value 935 to the Int32 value 935.
'    Converted the Char value x to the Int32 value 120.
'    No conversion to an Int32 exists for the DateTime value 5/12/2009 12:00:00 AM.
'    Converted the String value 104 to the Int32 value 104.
'    The String value 103.0 is not in a recognizable format.
'    Converted the String value -1 to the Int32 value -1.
'    The String value 1.00e2 is not in a recognizable format.
'    The String value One is not in a recognizable format.
'    Converted the Double value 100 to the Int32 value 100.
'    The Double value 1.63E+43 is outside the range of the Int32 type.

Commenti

Sevalue non è null, questo metodo esegue il wrapping di una chiamata ai IConvertible.ToInt32 implementazione del tipo sottostante di value.Ifvalue is not null, this method wraps a call to the IConvertible.ToInt32 implementation of the underlying type of value.

ToInt32(UInt16) ToInt32(UInt16) ToInt32(UInt16) ToInt32(UInt16)

Importante

Questa API non è conforme a CLS.

Converte il valore dell'intero senza segno a 16 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 16-bit unsigned integer to the equivalent 32-bit signed integer.

public:
 static int ToInt32(System::UInt16 value);
[System.CLSCompliant(false)]
public static int ToInt32 (ushort value);
static member ToInt32 : uint16 -> int
Public Shared Function ToInt32 (value As UShort) As Integer

Parametri

value
UInt16 UInt16 UInt16 UInt16

Intero senza segno a 16 bit da convertire.The 16-bit unsigned integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Esempi

Nell'esempio seguente converte ogni elemento in una matrice di interi senza segno a 16 bit in un numero intero.The following example converts each element in an array of 16-bit unsigned integers to an integer.

ushort[] numbers = { UInt16.MinValue, 121, 340, UInt16.MaxValue };
int result;
foreach (ushort number in numbers)
{
   try {
      result = Convert.ToInt32(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    Converted the UInt16 value 0 to the Int32 value 0.
//    Converted the UInt16 value 121 to the Int32 value 121.
//    Converted the UInt16 value 340 to the Int32 value 340.
//    Converted the UInt16 value 65535 to the Int32 value 65535.
Dim numbers() As UShort = { UInt16.MinValue, 121, 340, UInt16.MaxValue }
Dim result As Integer
For Each number As UShort In numbers
   Try
      result = Convert.ToInt32(number)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    Converted the UInt16 value 0 to the Int32 value 0.
'    Converted the UInt16 value 121 to the Int32 value 121.
'    Converted the UInt16 value 340 to the Int32 value 340.
'    Converted the UInt16 value 65535 to the Int32 value 65535.

ToInt32(Int32) ToInt32(Int32) ToInt32(Int32) ToInt32(Int32)

Restituisce l'intero con segno a 32 bit specificato; non viene eseguita alcuna conversione effettiva.Returns the specified 32-bit signed integer; no actual conversion is performed.

public:
 static int ToInt32(int value);
public static int ToInt32 (int value);
static member ToInt32 : int -> int
Public Shared Function ToInt32 (value As Integer) As Integer

Parametri

value
Int32 Int32 Int32 Int32

Intero con segno a 32 bit da restituire.The 32-bit signed integer to return.

Restituisce

value viene restituito invariato.value is returned unchanged.

ToInt32(Byte) ToInt32(Byte) ToInt32(Byte) ToInt32(Byte)

Converte il valore dell'intero senza segno a 8 bit specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified 8-bit unsigned integer to the equivalent 32-bit signed integer.

public:
 static int ToInt32(System::Byte value);
public static int ToInt32 (byte value);
static member ToInt32 : byte -> int
Public Shared Function ToInt32 (value As Byte) As Integer

Parametri

value
Byte Byte Byte Byte

Intero senza segno a 8 bit da convertire.The 8-bit unsigned integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Esempi

Nell'esempio seguente converte ogni elemento in una matrice di byte in un intero.The following example converts each element in an array of bytes to an integer.

byte[] bytes = { Byte.MinValue, 14, 122, Byte.MaxValue};
int result;

foreach (byte byteValue in bytes)
{
   result = Convert.ToInt32(byteValue);
   Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                     byteValue.GetType().Name, byteValue,
                     result.GetType().Name, result);
}
// The example displays the following output:
//       Converted the Byte value 0 to the Int32 value 0.
//       Converted the Byte value 14 to the Int32 value 14.
//       Converted the Byte value 122 to the Int32 value 122.
//       Converted the Byte value 255 to the Int32 value 255.
Dim bytes() As Byte = { Byte.MinValue, 14, 122, Byte.MaxValue}
Dim result As Integer

For Each byteValue As Byte In bytes
   result = Convert.ToInt32(byteValue)
   Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                     byteValue.GetType().Name, byteValue, _
                     result.GetType().Name, result)
Next
' The example displays the following output:
'       Converted the Byte value 0 to the Int32 value 0.
'       Converted the Byte value 14 to the Int32 value 14.
'       Converted the Byte value 122 to the Int32 value 122.
'       Converted the Byte value 255 to the Int32 value 255.

ToInt32(Char) ToInt32(Char) ToInt32(Char) ToInt32(Char)

Converte il valore del carattere Unicode specificato nell'intero con segno a 32 bit equivalente.Converts the value of the specified Unicode character to the equivalent 32-bit signed integer.

public:
 static int ToInt32(char value);
public static int ToInt32 (char value);
static member ToInt32 : char -> int
Public Shared Function ToInt32 (value As Char) As Integer

Parametri

value
Char Char Char Char

Carattere Unicode da convertire.The Unicode character to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Esempi

Nell'esempio seguente converte ogni elemento in una matrice di Char valori in un numero intero.The following example converts each element in an array of Char values to an integer.

char[] chars = { 'a', 'z', '\u0007', '\u03FF',
                 '\u7FFF', '\uFFFE' };
int result;
                        
foreach (char ch in chars)
{
   try {
      result = Convert.ToInt32(ch);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        ch.GetType().Name, ch,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("Unable to convert u+{0} to an Int32.",
                        ((int)ch).ToString("X4"));
   }
}   
// The example displays the following output:
//       Converted the Char value 'a' to the Int32 value 97.
//       Converted the Char value 'z' to the Int32 value 122.
//       Converted the Char value '' to the Int32 value 7.
//       Converted the Char value '?' to the Int32 value 1023.
//       Converted the Char value '?' to the Int32 value 32767.
//       Converted the Char value '?' to the Int32 value 65534.
Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023), _
                        ChrW(Short.MaxValue), ChrW(&hFFFE) }
Dim result As Integer
                        
For Each ch As Char in chars
   Try
      result = Convert.ToInt32(ch)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        ch.GetType().Name, ch, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("Unable to convert u+{0} to an Int32.", _
                        AscW(ch).ToString("X4"))
   End Try
Next   
' The example displays the following output:
'       Converted the Char value 'a' to the Int32 value 97.
'       Converted the Char value 'z' to the Int32 value 122.
'       Converted the Char value '' to the Int32 value 7.
'       Converted the Char value '?' to the Int32 value 1023.
'       Converted the Char value '?' to the Int32 value 32767.
'       Converted the Char value '?' to the Int32 value 65534.

Commenti

Il ToInt32(Char) metodo restituisce un intero con segno a 32 bit che rappresenta l'unità di codice codificata UTF-16 del value argomento.The ToInt32(Char) method returns a 32-bit signed integer that represents the UTF-16 encoded code unit of the value argument. Se value non è un surrogato basso o un surrogato alto, questo valore restituito rappresenta anche il punto di codice Unicode del valore.If value is not a low surrogate or a high surrogate, this return value also represents the Unicode code point of value.

ToInt32(DateTime) ToInt32(DateTime) ToInt32(DateTime) ToInt32(DateTime)

La chiamata di questo metodo genera sempre un'eccezione InvalidCastException.Calling this method always throws InvalidCastException.

public:
 static int ToInt32(DateTime value);
public static int ToInt32 (DateTime value);
static member ToInt32 : DateTime -> int
Public Shared Function ToInt32 (value As DateTime) As Integer

Parametri

value
DateTime DateTime DateTime DateTime

Valore di data e ora da convertire.The date and time value to convert.

Restituisce

Questa conversione non è supportata.This conversion is not supported. Non vengono restituiti valori.No value is returned.

Eccezioni

Questa conversione non è supportata.This conversion is not supported.

ToInt32(Boolean) ToInt32(Boolean) ToInt32(Boolean) ToInt32(Boolean)

Converte il valore booleano specificato nell'intero con segno a 32 bit equivalente.Converts the specified Boolean value to the equivalent 32-bit signed integer.

public:
 static int ToInt32(bool value);
public static int ToInt32 (bool value);
static member ToInt32 : bool -> int
Public Shared Function ToInt32 (value As Boolean) As Integer

Parametri

value
Boolean Boolean Boolean Boolean

Valore booleano da convertire.The Boolean value to convert.

Restituisce

Il numero 1 se value è true; in caso contrario, 0.The number 1 if value is true; otherwise, 0.

Esempi

L'esempio seguente converte la Boolean i valori true e false a numeri interi.The following example converts the Boolean values true and false to integers.

bool falseFlag = false;
bool trueFlag = true;

Console.WriteLine("{0} converts to {1}.", falseFlag,
                  Convert.ToInt32(falseFlag));
Console.WriteLine("{0} converts to {1}.", trueFlag,
                  Convert.ToInt32(trueFlag));
// The example displays the following output:
//       False converts to 0.
//       True converts to 1.
Dim falseFlag As Boolean = False
Dim trueFlag As Boolean = True

Console.WriteLine("{0} converts to {1}.", falseFlag, _
                  Convert.ToInt32(falseFlag))
Console.WriteLine("{0} converts to {1}.", trueFlag, _
                  Convert.ToInt32(trueFlag))
' The example displays the following output:
'       False converts to 0.
'       True converts to 1.

ToInt32(Int64) ToInt32(Int64) ToInt32(Int64) ToInt32(Int64)

Converte il valore dell'intero con segno a 64 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 64-bit signed integer to an equivalent 32-bit signed integer.

public:
 static int ToInt32(long value);
public static int ToInt32 (long value);
static member ToInt32 : int64 -> int
Public Shared Function ToInt32 (value As Long) As Integer

Parametri

value
Int64 Int64 Int64 Int64

Intero con segno a 64 bit da convertire.The 64-bit signed integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Eccezioni

value è maggiore di MaxValue o minore di MinValue.value is greater than MaxValue or less than MinValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento in una matrice di valori long integer in un numero intero.The following example attempts to convert each element in an array of long integers to an integer.

long[] numbers = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue };
int result;
foreach (long number in numbers)
{
   try {
      result = Convert.ToInt32(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    The Int64 value -9223372036854775808 is outside the range of the Int32 type.
//    Converted the Int64 value -1 to the Int32 value -1.
//    Converted the Int64 value 0 to the Int32 value 0.
//    Converted the Int64 value 121 to the Int32 value 121.
//    Converted the Int64 value 340 to the Int32 value 340.
//    The Int64 value 9223372036854775807 is outside the range of the Int32 type.
Dim numbers() As Long = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue }
Dim result As Integer
For Each number As Long In numbers
   Try
      result = Convert.ToInt32(number)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Int32 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    The Int64 value -9223372036854775808 is outside the range of the Int32 type.
'    Converted the Int64 value -1 to the Int32 value -1.
'    Converted the Int64 value 0 to the Int32 value 0.
'    Converted the Int64 value 121 to the Int32 value 121.
'    Converted the Int64 value 340 to the Int32 value 340.
'    The Int64 value 9223372036854775807 is outside the range of the Int32 type.

ToInt32(Double) ToInt32(Double) ToInt32(Double) ToInt32(Double)

Converte il valore del numero a virgola mobile a precisione doppia specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified double-precision floating-point number to an equivalent 32-bit signed integer.

public:
 static int ToInt32(double value);
public static int ToInt32 (double value);
static member ToInt32 : double -> int
Public Shared Function ToInt32 (value As Double) As Integer

Parametri

value
Double Double Double Double

Numero a virgola mobile a precisione doppia da convertire.The double-precision floating-point number to convert.

Restituisce

value, arrotondato all'intero con segno a 32 bit più vicino.value, rounded to the nearest 32-bit signed integer. Se value si trova a metà tra due numeri interi, viene restituito il numero intero pari; vale a dire, 4,5 viene convertito in 4, mentre 5,5 viene convertito in 6.If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

Eccezioni

value è maggiore di MaxValue o minore di MinValue.value is greater than MaxValue or less than MinValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento in una matrice di Double valori in un numero intero.The following example attempts to convert each element in an array of Double values to an integer.

double[] values= { Double.MinValue, -1.38e10, -1023.299, -12.98,
                   0, 9.113e-16, 103.919, 17834.191, Double.MaxValue };
int result;

foreach (double value in values)
{
   try {
      result = Convert.ToInt32(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the Int32 type.", value);
   }   
}                                 
//    -1.79769313486232E+308 is outside the range of the Int32 type.
//    -13800000000 is outside the range of the Int32 type.
//    Converted the Double value '-1023.299' to the Int32 value -1023.
//    Converted the Double value '-12.98' to the Int32 value -13.
//    Converted the Double value '0' to the Int32 value 0.
//    Converted the Double value '9.113E-16' to the Int32 value 0.
//    Converted the Double value '103.919' to the Int32 value 104.
//    Converted the Double value '17834.191' to the Int32 value 17834.
//    1.79769313486232E+308 is outside the range of the Int32 type.
Dim values() As Double = { Double.MinValue, -1.38e10, -1023.299, -12.98, _
                           0, 9.113e-16, 103.919, 17834.191, Double.MaxValue }
Dim result As Integer

For Each value As Double In values
   Try
      result = Convert.ToInt32(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the Int32 type.", value)
   End Try   
Next                                 
'    -1.79769313486232E+308 is outside the range of the Int32 type.
'    -13800000000 is outside the range of the Int32 type.
'    Converted the Double value '-1023.299' to the Int32 value -1023.
'    Converted the Double value '-12.98' to the Int32 value -13.
'    Converted the Double value '0' to the Int32 value 0.
'    Converted the Double value '9.113E-16' to the Int32 value 0.
'    Converted the Double value '103.919' to the Int32 value 104.
'    Converted the Double value '17834.191' to the Int32 value 17834.
'    1.79769313486232E+308 is outside the range of the Int32 type.
Vedi anche

ToInt32(Int16) ToInt32(Int16) ToInt32(Int16) ToInt32(Int16)

Converte il valore dell'intero con segno a 16 bit specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified 16-bit signed integer to an equivalent 32-bit signed integer.

public:
 static int ToInt32(short value);
public static int ToInt32 (short value);
static member ToInt32 : int16 -> int
Public Shared Function ToInt32 (value As Short) As Integer

Parametri

value
Int16 Int16 Int16 Int16

Intero con segno a 16 bit da convertire.The 16-bit signed integer to convert.

Restituisce

Intero con segno a 32 bit equivalente a value.A 32-bit signed integer that is equivalent to value.

Esempi

Nell'esempio seguente converte ogni elemento in una matrice di interi con segno a 16 bit in un numero intero.The following example converts each element in an array of 16-bit signed integers to an integer.

short[] numbers= { Int16.MinValue, -1, 0, 121, 340, Int16.MaxValue };
int result;

foreach (short number in numbers)
{
   result = Convert.ToInt32(number);
   Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
}
// The example displays the following output:
//    Converted the Int16 value -32768 to a Int32 value -32768.
//    Converted the Int16 value -1 to a Int32 value -1.
//    Converted the Int16 value 0 to a Int32 value 0.
//    Converted the Int16 value 121 to a Int32 value 121.
//    Converted the Int16 value 340 to a Int32 value 340.
//    Converted the Int16 value 32767 to a Int32 value 32767.
Dim numbers() As Short = { Int16.MinValue, -1, 0, 121, 340, Int16.MaxValue }
Dim result As Integer

For Each number As Short In numbers
   result = Convert.ToInt32(number)
   Console.WriteLine("Converted the {0} value {1} to a {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
Next
' The example displays the following output:
'    Converted the Int16 value -32768 to a Int32 value -32768.
'    Converted the Int16 value -1 to a Int32 value -1.
'    Converted the Int16 value 0 to a Int32 value 0.
'    Converted the Int16 value 121 to a Int32 value 121.
'    Converted the Int16 value 340 to a Int32 value 340.
'    Converted the Int16 value 32767 to a Int32 value 32767.

ToInt32(Decimal) ToInt32(Decimal) ToInt32(Decimal) ToInt32(Decimal)

Converte il valore del numero decimale specificato in un intero con segno a 32 bit equivalente.Converts the value of the specified decimal number to an equivalent 32-bit signed integer.

public:
 static int ToInt32(System::Decimal value);
public static int ToInt32 (decimal value);
static member ToInt32 : decimal -> int
Public Shared Function ToInt32 (value As Decimal) As Integer

Parametri

value
Decimal Decimal Decimal Decimal

Numero decimale da convertire.The decimal number to convert.

Restituisce

value, arrotondato all'intero con segno a 32 bit più vicino.value, rounded to the nearest 32-bit signed integer. Se value si trova a metà tra due numeri interi, viene restituito il numero intero pari; vale a dire, 4,5 viene convertito in 4, mentre 5,5 viene convertito in 6.If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

Eccezioni

value è maggiore di MaxValue o minore di MinValue.value is greater than MaxValue or less than MinValue.

Esempi

Nell'esempio seguente tenta di convertire ogni elemento in una matrice di Decimal valori in un numero intero.The following example attempts to convert each element in an array of Decimal values to an integer.

decimal[] values= { Decimal.MinValue, -1034.23m, -12m, 0m, 147m,
                    199.55m, 9214.16m, Decimal.MaxValue };
int result;

foreach (decimal value in values)
{
   try {
      result = Convert.ToInt32(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the Int32 type.",
                        value);
   }   
}                                  
// The example displays the following output:
//    -79228162514264337593543950335 is outside the range of the Int32 type.
//    Converted the Decimal value '-1034.23' to the Int32 value -1034.
//    Converted the Decimal value '-12' to the Int32 value -12.
//    Converted the Decimal value '0' to the Int32 value 0.
//    Converted the Decimal value '147' to the Int32 value 147.
//    Converted the Decimal value '199.55' to the Int32 value 200.
//    Converted the Decimal value '9214.16' to the Int32 value 9214.
//    79228162514264337593543950335 is outside the range of the Int32 type.
Dim values() As Decimal = { Decimal.MinValue, -1034.23d, -12d, 0d, 147d, _
                            199.55d, 9214.16d, Decimal.MaxValue }
Dim result As Integer

For Each value As Decimal In values
   Try
      result = Convert.ToInt32(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the Int32 type.", _
                        value)
   End Try   
Next                                  
' The example displays the following output:
'    -79228162514264337593543950335 is outside the range of the Int32 type.
'    Converted the Decimal value '-1034.23' to the Int32 value -1034.
'    Converted the Decimal value '-12' to the Int32 value -12.
'    Converted the Decimal value '0' to the Int32 value 0.
'    Converted the Decimal value '147' to the Int32 value 147.
'    Converted the Decimal value '199.55' to the Int32 value 200.
'    Converted the Decimal value '9214.16' to the Int32 value 9214.
'    79228162514264337593543950335 is outside the range of the Int32 type.
Vedi anche

Si applica a