Convert.ToInt16 Metodo
Definizione
Converte un valore specificato in un intero con segno a 16 bit.Converts a specified value to a 16-bit signed integer.
Overload
ToInt16(String, Int32) |
Converte la rappresentazione di stringa di un numero in una base specificata nell'intero con segno a 16 bit equivalente.Converts the string representation of a number in a specified base to an equivalent 16-bit signed integer. |
ToInt16(String, IFormatProvider) |
Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 16 bit equivalente mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the specified string representation of a number to an equivalent 16-bit signed integer, using the specified culture-specific formatting information. |
ToInt16(Object, IFormatProvider) |
Converte il valore dell'oggetto specificato in un intero con segno a 16 bit mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the value of the specified object to a 16-bit signed integer, using the specified culture-specific formatting information. |
ToInt16(UInt64) |
Converte il valore dell'intero senza segno a 64 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 64-bit unsigned integer to an equivalent 16-bit signed integer. |
ToInt16(UInt32) |
Converte il valore dell'intero senza segno a 32 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 32-bit unsigned integer to an equivalent 16-bit signed integer. |
ToInt16(UInt16) |
Converte il valore dell'intero senza segno a 16 bit specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified 16-bit unsigned integer to the equivalent 16-bit signed integer. |
ToInt16(String) |
Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 16 bit equivalente.Converts the specified string representation of a number to an equivalent 16-bit signed integer. |
ToInt16(Single) |
Converte il valore del numero a virgola mobile a precisione singola specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified single-precision floating-point number to an equivalent 16-bit signed integer. |
ToInt16(SByte) |
Converte il valore dell'intero con segno a 8 bit specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified 8-bit signed integer to the equivalent 16-bit signed integer. |
ToInt16(Int32) |
Converte il valore dell'intero con segno a 32 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 32-bit signed integer to an equivalent 16-bit signed integer. |
ToInt16(Int64) |
Converte il valore dell'intero con segno a 64 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 64-bit signed integer to an equivalent 16-bit signed integer. |
ToInt16(Int16) |
Restituisce l'intero con segno a 16 bit specificato; non viene eseguita alcuna conversione effettiva.Returns the specified 16-bit signed integer; no actual conversion is performed. |
ToInt16(Double) |
Converte il valore del numero a virgola mobile e con precisione doppia specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified double-precision floating-point number to an equivalent 16-bit signed integer. |
ToInt16(Decimal) |
Converte il valore del numero decimale specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified decimal number to an equivalent 16-bit signed integer. |
ToInt16(DateTime) |
La chiamata di questo metodo genera sempre un'eccezione InvalidCastException.Calling this method always throws InvalidCastException. |
ToInt16(Char) |
Converte il valore del carattere Unicode specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified Unicode character to the equivalent 16-bit signed integer. |
ToInt16(Byte) |
Converte il valore dell'intero senza segno a 8 bit specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified 8-bit unsigned integer to the equivalent 16-bit signed integer. |
ToInt16(Boolean) |
Converte il valore booleano specificato nell'intero con segno a 16 bit equivalente.Converts the specified Boolean value to the equivalent 16-bit signed integer. |
ToInt16(Object) |
Converte il valore dell'oggetto specificato in un intero con segno a 16 bit.Converts the value of the specified object to a 16-bit signed integer. |
ToInt16(String, Int32)
Converte la rappresentazione di stringa di un numero in una base specificata nell'intero con segno a 16 bit equivalente.Converts the string representation of a number in a specified base to an equivalent 16-bit signed integer.
public:
static short ToInt16(System::String ^ value, int fromBase);
public static short ToInt16 (string value, int fromBase);
static member ToInt16 : string * int -> int16
Public Shared Function ToInt16 (value As String, fromBase As Integer) As Short
Parametri
- value
- String
Stringa che contiene il numero da convertire.A string that contains the number to convert.
- fromBase
- 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 16 bit equivalente al numero in value
oppure 0 (zero) se value
è null
.A 16-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.
-oppure--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.
-oppure--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.
Esempio
Nell'esempio seguente viene eseguito un tentativo di interpretare ogni elemento in una matrice di stringhe come stringa esadecimale e convertirlo in un intero con segno a 16 bit.The following example attempts to interpret each element in a string array as a hexadecimal string and to convert it to a 16-bit signed integer.
using System;
public class Example
{
public static void Main()
{
string[] hexStrings = { "8000", "0FFF", "f000", "00A30", "D", "-13",
"9AC61", "GAD" };
foreach (string hexString in hexStrings)
{
try {
short number = Convert.ToInt16(hexString, 16);
Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number);
}
catch (FormatException) {
Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.",
hexString);
}
catch (OverflowException) {
Console.WriteLine("'{0}' is outside the range of an Int16.", hexString);
}
catch (ArgumentException) {
Console.WriteLine("'{0}' is invalid in base 16.", hexString);
}
}
}
}
// The example displays the following output:
// Converted '8000' to -32,768.
// Converted '0FFF' to 4,095.
// Converted 'f000' to -4,096.
// Converted '00A30' to 2,608.
// Converted 'D' to 13.
// '-13' is invalid in base 16.
// '9AC61' is outside the range of an Int16.
// 'GAD' is not in the correct format for a hexadecimal number.
Module Example
Public Sub Main()
Dim hexStrings() As String = { "8000", "0FFF", "f000", "00A30", "D", _
"-13", "9AC61", "GAD" }
For Each hexString As String In hexStrings
Try
Dim number As Short = Convert.ToInt16(hexString, 16)
Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number)
Catch e As FormatException
Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.", _
hexString)
Catch e As OverflowException
Console.WriteLine("'{0}' is outside the range of an Int16.", hexString)
Catch e As ArgumentException
Console.WriteLine("'{0}' is invalid in base 16.", hexString)
End Try
Next
End Sub
End Module
' The example displays the following output:
' Converted '8000' to -32,768.
' Converted '0FFF' to 4,095.
' Converted 'f000' to -4,096.
' Converted '00A30' to 2,608.
' Converted 'D' to 13.
' '-13' is invalid in base 16.
' '9AC61' is outside the range of an Int16.
' 'GAD' is not in the correct format for a hexadecimal number.
Commenti
Se fromBase
è 16, è possibile anteporre al numero specificato dal value
parametro "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 le rappresentazioni numeriche non in base 10, il ToInt16(String, Int32) metodo presuppone che i numeri negativi usino la rappresentazione in complemento a due.Because the negative sign is not supported for non-base 10 numeric representations, the ToInt16(String, Int32) method assumes that negative numbers use two's complement representation. In altre parole, il metodo interpreta sempre il bit binario di ordine superiore di un numero intero (bit 15) come bit di segno.In other words, the method always interprets the highest-order binary bit of an integer (bit 15) as its sign bit. Di conseguenza, è possibile scrivere codice in cui un numero non in base 10 non compreso nell'intervallo del Int16 tipo di dati viene convertito in un Int16 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 Int16 data type is converted to an Int16 value without the method throwing an exception. Nell'esempio seguente viene incrementato Int16.MaxValue di uno, il numero risultante viene convertito nella relativa rappresentazione di stringa esadecimale, quindi viene chiamato il ToInt16(String, Int32) metodo.The following example increments Int16.MaxValue by one, converts the resulting number to its hexadecimal string representation, and then calls the ToInt16(String, Int32) method. Anziché generare un'eccezione, il metodo Visualizza il messaggio "0x8000 converte in-32768".Instead of throwing an exception, the method displays the message, "0x8000 converts to -32768."
// Create a hexadecimal value out of range of the Int16 type.
string value = Convert.ToString((int) short.MaxValue + 1, 16);
// Convert it back to a number.
try
{
short number = Convert.ToInt16(value, 16);
Console.WriteLine("0x{0} converts to {1}.", value, number);
}
catch (OverflowException)
{
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value);
}
' Create a hexadecimal value out of range of the Int16 type.
Dim value As String = Convert.ToString(CInt(Short.MaxValue) + 1, 16)
' Convert it back to a number.
Try
Dim number As Short = Convert.ToInt16(value, 16)
Console.WriteLine("0x{0} converts to {1}.", value, number)
Catch e As OverflowException
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value)
End Try
Quando si eseguono operazioni binarie o conversioni numeriche, è sempre responsabilità dello sviluppatore verificare che un metodo usi la rappresentazione numerica appropriata per interpretare un determinato valore.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 assicurarsi che il metodo gestisca gli overflow in modo appropriato recuperando prima il segno del valore numerico prima di convertirlo nella relativa rappresentazione in forma 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. Genera un'eccezione se il valore originale è positivo, ma la conversione in un integer restituisce un valore negativo.Throw an exception if the original value was positive but the conversion back to an integer yields a negative value.
// Create a hexadecimal value out of range of the Short type.
int sourceNumber = (int) short.MaxValue + 1;
bool isNegative = (Math.Sign(sourceNumber) == -1);
string value = Convert.ToString(sourceNumber, 16);
short targetNumber;
try
{
targetNumber = Convert.ToInt16(value, 16);
if (! isNegative && ((targetNumber & 0x8000) != 0))
throw new OverflowException();
else
Console.WriteLine("0x{0} converts to {1}.", value, targetNumber);
}
catch (OverflowException)
{
Console.WriteLine("Unable to convert '0x{0}' to a 16-bit integer.", value);
}
// Displays the following to the console:
// Unable to convert '0x8000' to a 16-bit integer.
' Create a hexadecimal value out of range of the Short type.
Dim sourceNumber As Integer = CInt(Short.MaxValue) + 1
Dim isNegative As Boolean = (Math.Sign(sourceNumber) = -1)
Dim value As String = Convert.ToString(sourceNumber, 16)
Dim targetNumber As Short
Try
targetNumber = Convert.ToInt16(value, 16)
If Not isNegative And ((targetNumber And &H8000) <> 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 a 16-bit integer.", value)
End Try
' Displays the following to the console:
' Unable to convert '0x8000' to a 16-bit integer.
Si applica a
ToInt16(String, IFormatProvider)
Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 16 bit equivalente mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the specified string representation of a number to an equivalent 16-bit signed integer, using the specified culture-specific formatting information.
public:
static short ToInt16(System::String ^ value, IFormatProvider ^ provider);
public static short ToInt16 (string value, IFormatProvider provider);
static member ToInt16 : string * IFormatProvider -> int16
Public Shared Function ToInt16 (value As String, provider As IFormatProvider) As Short
Parametri
- value
- String
Stringa che contiene il numero da convertire.A string that contains the number to convert.
- provider
- IFormatProvider
Oggetto che fornisce informazioni di formattazione specifiche delle impostazioni cultura.An object that supplies culture-specific formatting information.
Restituisce
Intero con segno a 16 bit equivalente al numero in value
oppure 0 (zero) se value
è null
.A 16-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.
Esempio
Nell'esempio seguente vengono convertite le rappresentazioni di stringa di interi a 16 bit con il ToInt16
metodo utilizzando un IFormatProvider oggetto.The following example converts string representations of 16-bit integers with the ToInt16
method, using an IFormatProvider object.
// Example of the Convert::ToInt16( String* ) and
// Convert::ToInt16( String*, IFormatProvider* ) methods.
using namespace System;
using namespace System::Globalization;
const __wchar_t * protoFmt = L"{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
String^ GetExceptionType( Exception^ ex )
{
String^ exceptionType = ex->GetType()->ToString();
return exceptionType->Substring( exceptionType->LastIndexOf( '.' ) + 1 );
}
void ConvertToInt16( String^ numericStr, IFormatProvider^ provider )
{
Object^ defaultValue;
Object^ providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert::ToInt16( numericStr );
}
catch ( Exception^ ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert::ToInt16( numericStr, provider );
}
catch ( Exception^ ex )
{
providerValue = GetExceptionType( ex );
}
Console::WriteLine( gcnew String( protoFmt ), numericStr, defaultValue, providerValue );
}
int main()
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo^ provider = gcnew NumberFormatInfo;
// These properties affect the conversion.
provider->NegativeSign = "neg ";
provider->PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider->NumberDecimalSeparator = ".";
provider->NumberGroupSeparator = ",";
array<Int32>^sizes = {3};
provider->NumberGroupSizes = sizes;
provider->NumberNegativePattern = 0;
Console::WriteLine( "This example of\n"
" Convert::ToInt16( String* ) and \n"
" Convert::ToInt16( String*, IFormatProvider* ) "
"\ngenerates the following output. It converts "
"several strings to \nshort values, using "
"default formatting or a NumberFormatInfo object.\n" );
Console::WriteLine( gcnew String( protoFmt ), "String to convert", "Default/exception", "Provider/exception" );
Console::WriteLine( gcnew String( protoFmt ), "-----------------", "-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
/*
This example of
Convert::ToInt16( String* ) and
Convert::ToInt16( String*, IFormatProvider* )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
using System;
using System.Globalization;
class ToInt16ProviderDemo
{
static string format = "{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
static string GetExceptionType( Exception ex )
{
string exceptionType = ex.GetType( ).ToString( );
return exceptionType.Substring(
exceptionType.LastIndexOf( '.' ) + 1 );
}
static void ConvertToInt16( string numericStr,
IFormatProvider provider )
{
object defaultValue;
object providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert.ToInt16( numericStr );
}
catch( Exception ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert.ToInt16( numericStr, provider );
}
catch( Exception ex )
{
providerValue = GetExceptionType( ex );
}
Console.WriteLine( format, numericStr,
defaultValue, providerValue );
}
public static void Main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo provider = new NumberFormatInfo();
// These properties affect the conversion.
provider.NegativeSign = "neg ";
provider.PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = ".";
provider.NumberGroupSeparator = ",";
provider.NumberGroupSizes = new int[ ] { 3 };
provider.NumberNegativePattern = 0;
Console.WriteLine("This example of\n" +
" Convert.ToInt16( string ) and \n" +
" Convert.ToInt16( string, IFormatProvider ) " +
"\ngenerates the following output. It converts " +
"several strings to \nshort values, using " +
"default formatting or a NumberFormatInfo object.\n" );
Console.WriteLine( format, "String to convert",
"Default/exception", "Provider/exception" );
Console.WriteLine( format, "-----------------",
"-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
}
/*
This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
' Example of the Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider ) methods.
Imports System.Globalization
Module ToInt16ProviderDemo
Dim format As String = "{0,-20}{1,-20}{2}"
' Get the exception type name; remove the namespace prefix.
Function GetExceptionType( ex As Exception ) As String
Dim exceptionType As String = ex.GetType( ).ToString( )
Return exceptionType.Substring( _
exceptionType.LastIndexOf( "."c ) + 1 )
End Function
Sub ConvertToInt16( numericStr As String, _
provider As IFormatProvider )
Dim defaultValue As Object
Dim providerValue As Object
' Convert numericStr to Int16 without a format provider.
Try
defaultValue = Convert.ToInt16( numericStr )
Catch ex As Exception
defaultValue = GetExceptionType( ex )
End Try
' Convert numericStr to Int16 with a format provider.
Try
providerValue = Convert.ToInt16( numericStr, provider )
Catch ex As Exception
providerValue = GetExceptionType( ex )
End Try
Console.WriteLine( format, numericStr, _
defaultValue, providerValue )
End Sub
Sub Main( )
' Create a NumberFormatInfo object and set several of its
' properties that apply to numbers.
Dim provider As NumberFormatInfo = new NumberFormatInfo( )
' These properties affect the conversion.
provider.NegativeSign = "neg "
provider.PositiveSign = "pos "
' These properties do not affect the conversion.
' The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = "."
provider.NumberGroupSeparator = ","
provider.NumberGroupSizes = New Integer( ) { 3 }
provider.NumberNegativePattern = 0
Console.WriteLine( "This example of" & vbCrLf & _
" Convert.ToInt16( String ) and " & vbCrLf & _
" Convert.ToInt16( String, IFormatProvider ) " & _
vbCrLf & "generates the following output. It " & _
"converts several strings to " & vbCrLf & "Short " & _
"values, using default formatting " & _
"or a NumberFormatInfo object." & vbCrLf )
Console.WriteLine( format, "String to convert", _
"Default/exception", "Provider/exception" )
Console.WriteLine( format, "-----------------", _
"-----------------", "------------------" )
' Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider )
ConvertToInt16( "+12345", provider )
ConvertToInt16( "pos 12345", provider )
ConvertToInt16( "-12345", provider )
ConvertToInt16( "neg 12345", provider )
ConvertToInt16( "12345.", provider )
ConvertToInt16( "12,345", provider )
ConvertToInt16( "(12345)", provider )
ConvertToInt16( "32768", provider )
ConvertToInt16( "-32769", provider )
End Sub
End Module
' This example of
' Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider )
' generates the following output. It converts several strings to
' Short values, using default formatting or a NumberFormatInfo object.
'
' String to convert Default/exception Provider/exception
' ----------------- ----------------- ------------------
' 12345 12345 12345
' +12345 12345 FormatException
' pos 12345 FormatException 12345
' -12345 -12345 FormatException
' neg 12345 FormatException -12345
' 12345. FormatException FormatException
' 12,345 FormatException FormatException
' (12345) FormatException FormatException
' 32768 OverflowException OverflowException
' -32769 OverflowException FormatException
Commenti
provider
è un' IFormatProvider istanza di che ottiene un NumberFormatInfo oggetto.provider
is an IFormatProvider instance that obtains a NumberFormatInfo object. L' 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
è null
, NumberFormatInfo viene utilizzato l'oggetto per le impostazioni cultura correnti.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 invece possibile chiamare il Int16.TryParse metodo.If you prefer not to handle an exception if the conversion fails, you can call the Int16.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.
Vedi anche
Si applica a
ToInt16(Object, IFormatProvider)
Converte il valore dell'oggetto specificato in un intero con segno a 16 bit mediante le informazioni di formattazione specifiche delle impostazioni cultura indicate.Converts the value of the specified object to a 16-bit signed integer, using the specified culture-specific formatting information.
public:
static short ToInt16(System::Object ^ value, IFormatProvider ^ provider);
public static short ToInt16 (object value, IFormatProvider provider);
static member ToInt16 : obj * IFormatProvider -> int16
Public Shared Function ToInt16 (value As Object, provider As IFormatProvider) As Short
Parametri
- value
- Object
Oggetto che implementa l'interfaccia IConvertible.An object that implements the IConvertible interface.
- provider
- IFormatProvider
Oggetto che fornisce informazioni di formattazione specifiche delle impostazioni cultura.An object that supplies culture-specific formatting information.
Restituisce
Intero con segno a 16 bit equivalente a value
oppure zero se value
è null
.A 16-bit signed integer that is equivalent to value
, or zero if value
is null
.
Eccezioni
Il formato di value
non è appropriato per un tipo Int16.value
is not in an appropriate format for an Int16 type.
value
non implementa IConvertible.value
does not implement IConvertible.
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.
Esempio
Nell'esempio seguente viene definita 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. Un oggetto di ogni classe viene passato al ToInt16
metodo.An object of each class is passed to the ToInt16
method. Questo metodo restituisce una media della matrice di Double valori, usando l'oggetto che implementa IFormatProvider per determinare il modo in cui 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
provider
consente all'utente di specificare le informazioni relative alla conversione specifiche delle impostazioni cultura relative al contenuto di value
.provider
enables the user to specify culture-specific conversion information about the contents of value
. Se, ad esempio, value
è un oggetto String che rappresenta un numero, provider
può fornire informazioni specifiche delle impostazioni cultura relative alla notazione utilizzata per rappresentare tale 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.
I tipi di base ignorano provider
; tuttavia, il parametro può essere usato se value
è un tipo definito dall'utente che implementa l' 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.
Si applica a
ToInt16(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 16 bit equivalente.Converts the value of the specified 64-bit unsigned integer to an equivalent 16-bit signed integer.
public:
static short ToInt16(System::UInt64 value);
public static short ToInt16 (ulong value);
[System.CLSCompliant(false)]
public static short ToInt16 (ulong value);
static member ToInt16 : uint64 -> int16
[<System.CLSCompliant(false)>]
static member ToInt16 : uint64 -> int16
Public Shared Function ToInt16 (value As ULong) As Short
Parametri
- value
- UInt64
Intero senza segno a 64 bit da convertire.The 64-bit unsigned integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-bit signed integer that is equivalent to value
.
- Attributi
Eccezioni
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di interi senza segno in un intero con segno a 16 bit.The following example attempts to convert each element in an array of unsigned long integers to a 16-bit signed integer.
ulong[] numbers = { UInt64.MinValue, 121, 340, UInt64.MaxValue };
short result;
foreach (ulong number in numbers)
{
try {
result = Convert.ToInt16(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 Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt64 value 0 to a Int16 value 0.
// Converted the UInt64 value 121 to a Int16 value 121.
// Converted the UInt64 value 340 to a Int16 value 340.
// The UInt64 value 18446744073709551615 is outside the range of the Int16 type.
Dim numbers() As ULong = { UInt64.MinValue, 121, 340, UInt64.MaxValue }
Dim result As Short
For Each number As ULong In numbers
Try
result = Convert.ToInt16(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 Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt64 value 0 to a Int16 value 0.
' Converted the UInt64 value 121 to a Int16 value 121.
' Converted the UInt64 value 340 to a Int16 value 340.
' The UInt64 value 18446744073709551615 is outside the range of the Int16 type.
Si applica a
ToInt16(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 16 bit equivalente.Converts the value of the specified 32-bit unsigned integer to an equivalent 16-bit signed integer.
public:
static short ToInt16(System::UInt32 value);
public static short ToInt16 (uint value);
[System.CLSCompliant(false)]
public static short ToInt16 (uint value);
static member ToInt16 : uint32 -> int16
[<System.CLSCompliant(false)>]
static member ToInt16 : uint32 -> int16
Public Shared Function ToInt16 (value As UInteger) As Short
Parametri
- value
- UInt32
Intero senza segno a 32 bit da convertire.The 32-bit unsigned integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-bit signed integer that is equivalent to value
.
- Attributi
Eccezioni
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di interi senza segno in un intero con segno a 16 bit.The following example attempts to convert each element in an array of unsigned integers to a 16-bit signed integer.
uint[] numbers = { UInt32.MinValue, 121, 340, UInt32.MaxValue };
short result;
foreach (uint number in numbers)
{
try {
result = Convert.ToInt16(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 Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt32 value 0 to a Int16 value 0.
// Converted the UInt32 value 121 to a Int16 value 121.
// Converted the UInt32 value 340 to a Int16 value 340.
// The UInt32 value 4294967295 is outside the range of the Int16 type.
Dim numbers() As UInteger = { UInt32.MinValue, 121, 340, UInt32.MaxValue }
Dim result As Short
For Each number As UInteger In numbers
Try
result = Convert.ToInt16(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 Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt32 value 0 to a Int16 value 0.
' Converted the UInt32 value 121 to a Int16 value 121.
' Converted the UInt32 value 340 to a Int16 value 340.
' The UInt32 value 4294967295 is outside the range of the Int16 type.
Si applica a
ToInt16(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 16 bit equivalente.Converts the value of the specified 16-bit unsigned integer to the equivalent 16-bit signed integer.
public:
static short ToInt16(System::UInt16 value);
public static short ToInt16 (ushort value);
[System.CLSCompliant(false)]
public static short ToInt16 (ushort value);
static member ToInt16 : uint16 -> int16
[<System.CLSCompliant(false)>]
static member ToInt16 : uint16 -> int16
Public Shared Function ToInt16 (value As UShort) As Short
Parametri
- value
- UInt16
Intero senza segno a 16 bit da convertire.The 16-bit unsigned integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-bit signed integer that is equivalent to value
.
- Attributi
Eccezioni
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di interi senza segno a 16 bit in un intero con segno a 16 bit.The following example attempts to convert each element in an array of unsigned 16-bit integers to a 16-bit signed integer.
ushort[] numbers = { UInt16.MinValue, 121, 340, UInt16.MaxValue };
short result;
foreach (ushort number in numbers)
{
try {
result = Convert.ToInt16(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 Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// Converted the UInt16 value 0 to a Int16 value 0.
// Converted the UInt16 value 121 to a Int16 value 121.
// Converted the UInt16 value 340 to a Int16 value 340.
// The UInt16 value 65535 is outside the range of the Int16 type.
Dim numbers() As UShort = { UInt16.MinValue, 121, 340, UInt16.MaxValue }
Dim result As Short
For Each number As UShort In numbers
Try
result = Convert.ToInt16(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 Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' Converted the UInt16 value 0 to a Int16 value 0.
' Converted the UInt16 value 121 to a Int16 value 121.
' Converted the UInt16 value 340 to a Int16 value 340.
' The UInt16 value 65535 is outside the range of the Int16 type.
Si applica a
ToInt16(String)
Converte la rappresentazione di stringa specificata di un numero in un intero con segno a 16 bit equivalente.Converts the specified string representation of a number to an equivalent 16-bit signed integer.
public:
static short ToInt16(System::String ^ value);
public static short ToInt16 (string value);
static member ToInt16 : string -> int16
Public Shared Function ToInt16 (value As String) As Short
Parametri
- value
- String
Stringa che contiene il numero da convertire.A string that contains the number to convert.
Restituisce
Intero con segno a 16 bit equivalente al numero in value
oppure 0 (zero) se value
è null
.A 16-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.
Esempio
Nell'esempio seguente vengono convertite le rappresentazioni di stringa di interi a 16 bit con il ToInt16
metodo, usando la formattazione predefinita.The following example converts string representations of 16-bit integers with the ToInt16
method, using default formatting.
// Example of the Convert::ToInt16( String* ) and
// Convert::ToInt16( String*, IFormatProvider* ) methods.
using namespace System;
using namespace System::Globalization;
const __wchar_t * protoFmt = L"{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
String^ GetExceptionType( Exception^ ex )
{
String^ exceptionType = ex->GetType()->ToString();
return exceptionType->Substring( exceptionType->LastIndexOf( '.' ) + 1 );
}
void ConvertToInt16( String^ numericStr, IFormatProvider^ provider )
{
Object^ defaultValue;
Object^ providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert::ToInt16( numericStr );
}
catch ( Exception^ ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert::ToInt16( numericStr, provider );
}
catch ( Exception^ ex )
{
providerValue = GetExceptionType( ex );
}
Console::WriteLine( gcnew String( protoFmt ), numericStr, defaultValue, providerValue );
}
int main()
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo^ provider = gcnew NumberFormatInfo;
// These properties affect the conversion.
provider->NegativeSign = "neg ";
provider->PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider->NumberDecimalSeparator = ".";
provider->NumberGroupSeparator = ",";
array<Int32>^sizes = {3};
provider->NumberGroupSizes = sizes;
provider->NumberNegativePattern = 0;
Console::WriteLine( "This example of\n"
" Convert::ToInt16( String* ) and \n"
" Convert::ToInt16( String*, IFormatProvider* ) "
"\ngenerates the following output. It converts "
"several strings to \nshort values, using "
"default formatting or a NumberFormatInfo object.\n" );
Console::WriteLine( gcnew String( protoFmt ), "String to convert", "Default/exception", "Provider/exception" );
Console::WriteLine( gcnew String( protoFmt ), "-----------------", "-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
/*
This example of
Convert::ToInt16( String* ) and
Convert::ToInt16( String*, IFormatProvider* )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
// Example of the Convert.ToInt16( string ) and
// Convert.ToInt16( string, IFormatProvider ) methods.
using System;
using System.Globalization;
class ToInt16ProviderDemo
{
static string format = "{0,-20}{1,-20}{2}";
// Get the exception type name; remove the namespace prefix.
static string GetExceptionType( Exception ex )
{
string exceptionType = ex.GetType( ).ToString( );
return exceptionType.Substring(
exceptionType.LastIndexOf( '.' ) + 1 );
}
static void ConvertToInt16( string numericStr,
IFormatProvider provider )
{
object defaultValue;
object providerValue;
// Convert numericStr to Int16 without a format provider.
try
{
defaultValue = Convert.ToInt16( numericStr );
}
catch( Exception ex )
{
defaultValue = GetExceptionType( ex );
}
// Convert numericStr to Int16 with a format provider.
try
{
providerValue = Convert.ToInt16( numericStr, provider );
}
catch( Exception ex )
{
providerValue = GetExceptionType( ex );
}
Console.WriteLine( format, numericStr,
defaultValue, providerValue );
}
public static void Main( )
{
// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
NumberFormatInfo provider = new NumberFormatInfo();
// These properties affect the conversion.
provider.NegativeSign = "neg ";
provider.PositiveSign = "pos ";
// These properties do not affect the conversion.
// The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = ".";
provider.NumberGroupSeparator = ",";
provider.NumberGroupSizes = new int[ ] { 3 };
provider.NumberNegativePattern = 0;
Console.WriteLine("This example of\n" +
" Convert.ToInt16( string ) and \n" +
" Convert.ToInt16( string, IFormatProvider ) " +
"\ngenerates the following output. It converts " +
"several strings to \nshort values, using " +
"default formatting or a NumberFormatInfo object.\n" );
Console.WriteLine( format, "String to convert",
"Default/exception", "Provider/exception" );
Console.WriteLine( format, "-----------------",
"-----------------", "------------------" );
// Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider );
ConvertToInt16( "+12345", provider );
ConvertToInt16( "pos 12345", provider );
ConvertToInt16( "-12345", provider );
ConvertToInt16( "neg 12345", provider );
ConvertToInt16( "12345.", provider );
ConvertToInt16( "12,345", provider );
ConvertToInt16( "(12345)", provider );
ConvertToInt16( "32768", provider );
ConvertToInt16( "-32769", provider );
}
}
/*
This example of
Convert.ToInt16( string ) and
Convert.ToInt16( string, IFormatProvider )
generates the following output. It converts several strings to
short values, using default formatting or a NumberFormatInfo object.
String to convert Default/exception Provider/exception
----------------- ----------------- ------------------
12345 12345 12345
+12345 12345 FormatException
pos 12345 FormatException 12345
-12345 -12345 FormatException
neg 12345 FormatException -12345
12345. FormatException FormatException
12,345 FormatException FormatException
(12345) FormatException FormatException
32768 OverflowException OverflowException
-32769 OverflowException FormatException
*/
' Example of the Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider ) methods.
Imports System.Globalization
Module ToInt16ProviderDemo
Dim format As String = "{0,-20}{1,-20}{2}"
' Get the exception type name; remove the namespace prefix.
Function GetExceptionType( ex As Exception ) As String
Dim exceptionType As String = ex.GetType( ).ToString( )
Return exceptionType.Substring( _
exceptionType.LastIndexOf( "."c ) + 1 )
End Function
Sub ConvertToInt16( numericStr As String, _
provider As IFormatProvider )
Dim defaultValue As Object
Dim providerValue As Object
' Convert numericStr to Int16 without a format provider.
Try
defaultValue = Convert.ToInt16( numericStr )
Catch ex As Exception
defaultValue = GetExceptionType( ex )
End Try
' Convert numericStr to Int16 with a format provider.
Try
providerValue = Convert.ToInt16( numericStr, provider )
Catch ex As Exception
providerValue = GetExceptionType( ex )
End Try
Console.WriteLine( format, numericStr, _
defaultValue, providerValue )
End Sub
Sub Main( )
' Create a NumberFormatInfo object and set several of its
' properties that apply to numbers.
Dim provider As NumberFormatInfo = new NumberFormatInfo( )
' These properties affect the conversion.
provider.NegativeSign = "neg "
provider.PositiveSign = "pos "
' These properties do not affect the conversion.
' The input string cannot have decimal and group separators.
provider.NumberDecimalSeparator = "."
provider.NumberGroupSeparator = ","
provider.NumberGroupSizes = New Integer( ) { 3 }
provider.NumberNegativePattern = 0
Console.WriteLine( "This example of" & vbCrLf & _
" Convert.ToInt16( String ) and " & vbCrLf & _
" Convert.ToInt16( String, IFormatProvider ) " & _
vbCrLf & "generates the following output. It " & _
"converts several strings to " & vbCrLf & "Short " & _
"values, using default formatting " & _
"or a NumberFormatInfo object." & vbCrLf )
Console.WriteLine( format, "String to convert", _
"Default/exception", "Provider/exception" )
Console.WriteLine( format, "-----------------", _
"-----------------", "------------------" )
' Convert strings, with and without an IFormatProvider.
ConvertToInt16( "12345", provider )
ConvertToInt16( "+12345", provider )
ConvertToInt16( "pos 12345", provider )
ConvertToInt16( "-12345", provider )
ConvertToInt16( "neg 12345", provider )
ConvertToInt16( "12345.", provider )
ConvertToInt16( "12,345", provider )
ConvertToInt16( "(12345)", provider )
ConvertToInt16( "32768", provider )
ConvertToInt16( "-32769", provider )
End Sub
End Module
' This example of
' Convert.ToInt16( String ) and
' Convert.ToInt16( String, IFormatProvider )
' generates the following output. It converts several strings to
' Short values, using default formatting or a NumberFormatInfo object.
'
' String to convert Default/exception Provider/exception
' ----------------- ----------------- ------------------
' 12345 12345 12345
' +12345 12345 FormatException
' pos 12345 FormatException 12345
' -12345 -12345 FormatException
' neg 12345 FormatException -12345
' 12345. FormatException FormatException
' 12,345 FormatException FormatException
' (12345) FormatException FormatException
' 32768 OverflowException OverflowException
' -32769 OverflowException FormatException
Commenti
L'utilizzo del ToInt16(String) metodo equivale al passaggio value
al Int16.Parse(String) metodo.Using the ToInt16(String) method is equivalent to passing value
to the Int16.Parse(String) method. value
viene interpretato utilizzando le convenzioni di formattazione delle impostazioni cultura del thread corrente.value
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 invece possibile chiamare il Int16.TryParse metodo.If you prefer not to handle an exception if the conversion fails, you can call the Int16.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.
Vedi anche
Si applica a
ToInt16(Single)
Converte il valore del numero a virgola mobile a precisione singola specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified single-precision floating-point number to an equivalent 16-bit signed integer.
public:
static short ToInt16(float value);
public static short ToInt16 (float value);
static member ToInt16 : single -> int16
Public Shared Function ToInt16 (value As Single) As Short
Parametri
- value
- 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 16 bit più vicino.value
, rounded to the nearest 16-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.
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di Single valori in un intero con segno a 16 bit.The following example attempts to convert each element in an array of Single values to a 16-bit signed integer.
float[] values = { Single.MinValue, -1.38e10f, -1023.299f, -12.98f,
0f, 9.113e-16f, 103.919f, 17834.191f, Single.MaxValue };
short result;
foreach (float value in values)
{
try {
result = Convert.ToInt16(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 Int16 type.", value);
}
}
// The example displays the following output:
// -3.40282346638529E+38 is outside the range of the Int16 type.
// -13799999488 is outside the range of the Int16 type.
// Converted the Double value -1023.29901123047 to the Int16 value -1023.
// Converted the Double value -12.9799995422363 to the Int16 value -13.
// Converted the Double value 0 to the Int16 value 0.
// Converted the Double value 9.11299983940444E-16 to the Int16 value 0.
// Converted the Double value 103.918998718262 to the Int16 value 104.
// Converted the Double value 17834.19140625 to the Int16 value 17834.
// 3.40282346638529E+38 is outside the range of the Int16 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 Short
For Each value As Single In values
Try
result = Convert.ToInt16(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 Int16 type.", value)
End Try
Next
' The example displays the following output:
' -3.40282346638529E+38 is outside the range of the Int16 type.
' -13799999488 is outside the range of the Int16 type.
' Converted the Double value -1023.29901123047 to the Int16 value -1023.
' Converted the Double value -12.9799995422363 to the Int16 value -13.
' Converted the Double value 0 to the Int16 value 0.
' Converted the Double value 9.11299983940444E-16 to the Int16 value 0.
' Converted the Double value 103.918998718262 to the Int16 value 104.
' Converted the Double value 17834.19140625 to the Int16 value 17834.
' 3.40282346638529E+38 is outside the range of the Int16 type.
Vedi anche
Si applica a
ToInt16(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 16 bit equivalente.Converts the value of the specified 8-bit signed integer to the equivalent 16-bit signed integer.
public:
static short ToInt16(System::SByte value);
public static short ToInt16 (sbyte value);
[System.CLSCompliant(false)]
public static short ToInt16 (sbyte value);
static member ToInt16 : sbyte -> int16
[<System.CLSCompliant(false)>]
static member ToInt16 : sbyte -> int16
Public Shared Function ToInt16 (value As SByte) As Short
Parametri
- value
- 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
.
- Attributi
Esempio
Nell'esempio seguente ogni elemento di una matrice di byte con segno viene convertito in un intero con segno a 16 bit.The following example converts each element in an array of signed bytes to a 16-bit signed integer.
sbyte[] numbers = { SByte.MinValue, -1, 0, 10, SByte.MaxValue };
short result;
foreach (sbyte number in numbers)
{
result = Convert.ToInt16(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 Int16 value -128.
// Converted the SByte value -1 to the Int16 value -1.
// Converted the SByte value 0 to the Int16 value 0.
// Converted the SByte value 10 to the Int16 value 10.
// Converted the SByte value 127 to the Int16 value 127.
Dim numbers() As SByte = { SByte.MinValue, -1, 0, 10, SByte.MaxValue }
Dim result As Short
For Each number As SByte In numbers
result = Convert.ToInt16(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 Int16 value -128.
' Converted the SByte value -1 to the Int16 value -1.
' Converted the SByte value 0 to the Int16 value 0.
' Converted the SByte value 10 to the Int16 value 10.
' Converted the SByte value 127 to the Int16 value 127.
Si applica a
ToInt16(Int32)
Converte il valore dell'intero con segno a 32 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 32-bit signed integer to an equivalent 16-bit signed integer.
public:
static short ToInt16(int value);
public static short ToInt16 (int value);
static member ToInt16 : int -> int16
Public Shared Function ToInt16 (value As Integer) As Short
Parametri
- value
- Int32
Intero con segno a 32 bit da convertire.The 32-bit signed integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.The 16-bit signed integer equivalent of value
.
Eccezioni
value
è maggiore di MaxValue o minore di MinValue.value
is greater than MaxValue or less than MinValue.
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di numeri interi in un intero con segno a 16 bit.The following example attempts to convert each element in an array of integers to a 16-bit signed integer.
int[] numbers = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue };
short result;
foreach (int number in numbers)
{
try {
result = Convert.ToInt16(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 Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// The Int32 value -2147483648 is outside the range of the Int16 type.
// Converted the Int32 value -1 to a Int16 value -1.
// Converted the Int32 value 0 to a Int16 value 0.
// Converted the Int32 value 121 to a Int16 value 121.
// Converted the Int32 value 340 to a Int16 value 340.
// The Int32 value 2147483647 is outside the range of the Int16 type.
Dim numbers() As Integer = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue }
Dim result As Short
For Each number As Integer In numbers
Try
result = Convert.ToInt16(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 Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' The Int32 value -2147483648 is outside the range of the Int16 type.
' Converted the Int32 value -1 to a Int16 value -1.
' Converted the Int32 value 0 to a Int16 value 0.
' Converted the Int32 value 121 to a Int16 value 121.
' Converted the Int32 value 340 to a Int16 value 340.
' The Int32 value 2147483647 is outside the range of the Int16 type.
Si applica a
ToInt16(Int64)
Converte il valore dell'intero con segno a 64 bit specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified 64-bit signed integer to an equivalent 16-bit signed integer.
public:
static short ToInt16(long value);
public static short ToInt16 (long value);
static member ToInt16 : int64 -> int16
Public Shared Function ToInt16 (value As Long) As Short
Parametri
- value
- Int64
Intero con segno a 64 bit da convertire.The 64-bit signed integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-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.
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di valori long integer in un intero con segno a 16 bit.The following example attempts to convert each element in an array of long integers to a 16-bit signed integer.
long[] numbers = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue };
short result;
foreach (long number in numbers)
{
try {
result = Convert.ToInt16(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 Int16 type.",
number.GetType().Name, number);
}
}
// The example displays the following output:
// The Int64 value -9223372036854775808 is outside the range of the Int16 type.
// Converted the Int64 value -1 to the Int16 value -1.
// Converted the Int64 value 0 to the Int16 value 0.
// Converted the Int64 value 121 to the Int16 value 121.
// Converted the Int64 value 340 to the Int16 value 340.
// The Int64 value 9223372036854775807 is outside the range of the Int16 type.
Dim numbers() As Long = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue }
Dim result As Short
For Each number As Long In numbers
Try
result = Convert.ToInt16(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 Int16 type.", _
number.GetType().Name, number)
End Try
Next
' The example displays the following output:
' The Int64 value -9223372036854775808 is outside the range of the Int16 type.
' Converted the Int64 value -1 to the Int16 value -1.
' Converted the Int64 value 0 to the Int16 value 0.
' Converted the Int64 value 121 to the Int16 value 121.
' Converted the Int64 value 340 to the Int16 value 340.
' The Int64 value 9223372036854775807 is outside the range of the Int16 type.
Si applica a
ToInt16(Int16)
Restituisce l'intero con segno a 16 bit specificato; non viene eseguita alcuna conversione effettiva.Returns the specified 16-bit signed integer; no actual conversion is performed.
public:
static short ToInt16(short value);
public static short ToInt16 (short value);
static member ToInt16 : int16 -> int16
Public Shared Function ToInt16 (value As Short) As Short
Parametri
- value
- Int16
Intero con segno a 16 bit da restituire.The 16-bit signed integer to return.
Restituisce
value
viene restituito invariato.value
is returned unchanged.
Si applica a
ToInt16(Double)
Converte il valore del numero a virgola mobile e con precisione doppia specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified double-precision floating-point number to an equivalent 16-bit signed integer.
public:
static short ToInt16(double value);
public static short ToInt16 (double value);
static member ToInt16 : double -> int16
Public Shared Function ToInt16 (value As Double) As Short
Parametri
- value
- 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 16 bit più vicino.value
, rounded to the nearest 16-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.
Esempio
Nell'esempio seguente ogni elemento di una matrice di valori viene convertito in Double un intero con segno a 16 bit.The following example converts each element in an array of Double values to a 16-bit signed integer. Nell'esempio viene illustrato che qualsiasi parte frazionaria di un Double valore viene arrotondata prima di eseguire la conversione.The example illustrates that any fractional part of a Double value is rounded before performing the conversion.
double[] values = { Double.MinValue, -1.38e10, -1023.299, -12.98,
0, 9.113e-16, 103.919, 17834.191, Double.MaxValue };
short result;
foreach (double value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted {0} to {1}.", value, result);
}
catch (OverflowException)
{
Console.WriteLine("{0} is outside the range of the Int16 type.", value);
}
}
// -1.79769313486232E+308 is outside the range of the Int16 type.
// -13800000000 is outside the range of the Int16 type.
// Converted -1023.299 to -1023.
// Converted -12.98 to -13.
// Converted 0 to 0.
// Converted 9.113E-16 to 0.
// Converted 103.919 to 104.
// Converted 17834.191 to 17834.
// 1.79769313486232E+308 is outside the range of the Int16 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 Short
For Each value As Double In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted {0} to {1}.", value, result)
Catch e As OverflowException
Console.WriteLine("{0} is outside the range of the Int16 type.", value)
End Try
Next
' -1.79769313486232E+308 is outside the range of the Int16 type.
' -13800000000 is outside the range of the Int16 type.
' Converted -1023.299 to -1023.
' Converted -12.98 to -13.
' Converted 0 to 0.
' Converted 9.113E-16 to 0.
' Converted 103.919 to 104.
' Converted 17834.191 to 17834.
' 1.79769313486232E+308 is outside the range of the Int16 type.
Vedi anche
Si applica a
ToInt16(Decimal)
Converte il valore del numero decimale specificato in un intero con segno a 16 bit equivalente.Converts the value of the specified decimal number to an equivalent 16-bit signed integer.
public:
static short ToInt16(System::Decimal value);
public static short ToInt16 (decimal value);
static member ToInt16 : decimal -> int16
Public Shared Function ToInt16 (value As Decimal) As Short
Parametri
- value
- Decimal
Numero decimale da convertire.The decimal number to convert.
Restituisce
value
, arrotondato all'intero con segno a 16 bit più vicino.value
, rounded to the nearest 16-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.
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di Decimal valori in un intero con segno a 16 bit.The following example attempts to convert each element in an array of Decimal values to a 16-bit signed integer. Nell'esempio viene illustrato che qualsiasi parte frazionaria di un Decimal valore viene arrotondata quando si esegue la conversione.The example illustrates that any fractional part of a Decimal value is rounded when performing the conversion.
decimal[] values = { Decimal.MinValue, -1034.23m, -12m, 0m, 147m,
9214.16m, Decimal.MaxValue };
short result;
foreach (decimal value in values)
{
try {
result = Convert.ToInt16(value);
Console.WriteLine("Converted {0} to {1}.", value, result);
}
catch (OverflowException)
{
Console.WriteLine("{0} is outside the range of the Int16 type.",
value);
}
}
// The example displays the following output:
// -79228162514264337593543950335 is outside the range of the Int16 type.
// Converted -1034.23 to -1034.
// Converted -12 to -12.
// Converted 0 to 0.
// Converted 147 to 147.
// Converted 9214.16 to 9214.
// 79228162514264337593543950335 is outside the range of the Int16 type.
Dim values() As Decimal = { Decimal.MinValue, -1034.23d, -12d, 0d, 147d, _
9214.16d, Decimal.MaxValue }
Dim result As Short
For Each value As Decimal In values
Try
result = Convert.ToInt16(value)
Console.WriteLine("Converted {0} to {1}.", value, result)
Catch e As OverflowException
Console.WriteLine("{0} is outside the range of the Int16 type.", _
value)
End Try
Next
' The example displays the following output:
' -79228162514264337593543950335 is outside the range of the Int16 type.
' Converted -1034.23 to -1034.
' Converted -12 to -12.
' Converted 0 to 0.
' Converted 147 to 147.
' Converted 9214.16 to 9214.
' 79228162514264337593543950335 is outside the range of the Int16 type.
Vedi anche
Si applica a
ToInt16(DateTime)
La chiamata di questo metodo genera sempre un'eccezione InvalidCastException.Calling this method always throws InvalidCastException.
public:
static short ToInt16(DateTime value);
public static short ToInt16 (DateTime value);
static member ToInt16 : DateTime -> int16
Public Shared Function ToInt16 (value As DateTime) As Short
Parametri
- value
- 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.
Si applica a
ToInt16(Char)
Converte il valore del carattere Unicode specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified Unicode character to the equivalent 16-bit signed integer.
public:
static short ToInt16(char value);
public static short ToInt16 (char value);
static member ToInt16 : char -> int16
Public Shared Function ToInt16 (value As Char) As Short
Parametri
- value
- Char
Carattere Unicode da convertire.The Unicode character to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-bit signed integer that is equivalent to value
.
Eccezioni
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di Char valori in un intero con segno a 16 bit.The following example attempts to convert each element in an array of Char values to a 16-bit signed integer.
char[] chars = { 'a', 'z', '\x0007', '\x03FF',
'\x7FFF', '\xFFFE' };
short result;
foreach (char ch in chars)
{
try {
result = Convert.ToInt16(ch);
Console.WriteLine("'{0}' converts to {1}.", ch, result);
}
catch (OverflowException) {
Console.WriteLine("Unable to convert u+{0} to an Int16.",
((int)ch).ToString("X4"));
}
}
// The example displays the following output:
// 'a' converts to 97.
// 'z' converts to 122.
// '' converts to 7.
// '?' converts to 1023.
// '?' converts to 32767.
// Unable to convert u+FFFE to a UInt16.
Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023), _
ChrW(Short.MaxValue), ChrW(&hFFFE) }
Dim result As Short
For Each ch As Char in chars
Try
result = Convert.ToInt16(ch)
Console.WriteLine("'{0}' converts to {1}.", ch, result)
Catch e As OverflowException
Console.WriteLine("Unable to convert u+{0} to an Int16.", _
AscW(ch).ToString("X4"))
End Try
Next
' The example displays the following output:
' 'a' converts to 97.
' 'z' converts to 122.
' '' converts to 7.
' '?' converts to 1023.
' '?' converts to 32767.
' Unable to convert u+FFFE to a UInt16.
Si applica a
ToInt16(Byte)
Converte il valore dell'intero senza segno a 8 bit specificato nell'intero con segno a 16 bit equivalente.Converts the value of the specified 8-bit unsigned integer to the equivalent 16-bit signed integer.
public:
static short ToInt16(System::Byte value);
public static short ToInt16 (byte value);
static member ToInt16 : byte -> int16
Public Shared Function ToInt16 (value As Byte) As Short
Parametri
- value
- Byte
Intero senza segno a 8 bit da convertire.The 8-bit unsigned integer to convert.
Restituisce
Intero con segno a 16 bit equivalente a value
.A 16-bit signed integer that is equivalent to value
.
Esempio
Nell'esempio seguente ogni elemento di una matrice di valori viene convertito in Byte un intero con segno a 16 bit.The following example converts each element in an array of Byte values to a 16-bit signed integer.
byte[] bytes = { Byte.MinValue, 14, 122, Byte.MaxValue};
short result;
foreach (byte byteValue in bytes)
{
result = Convert.ToInt16(byteValue);
Console.WriteLine("The Byte value {0} converts to {1}.",
byteValue, result);
}
// The example displays the following output:
// The Byte value 0 converts to 0.
// The Byte value 14 converts to 14.
// The Byte value 122 converts to 122.
// The Byte value 255 converts to 255.
Dim bytes() As Byte = { Byte.MinValue, 14, 122, Byte.MaxValue}
Dim result As Short
For Each byteValue As Byte In bytes
result = Convert.ToInt16(byteValue)
Console.WriteLine("The Byte value {0} converts to {1}.", _
byteValue, result)
Next
' The example displays the following output:
' The Byte value 0 converts to 0.
' The Byte value 14 converts to 14.
' The Byte value 122 converts to 122.
' The Byte value 255 converts to 255.
Si applica a
ToInt16(Boolean)
Converte il valore booleano specificato nell'intero con segno a 16 bit equivalente.Converts the specified Boolean value to the equivalent 16-bit signed integer.
public:
static short ToInt16(bool value);
public static short ToInt16 (bool value);
static member ToInt16 : bool -> int16
Public Shared Function ToInt16 (value As Boolean) As Short
Parametri
- value
- 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.
Esempio
Nell'esempio seguente vengono convertiti i valori booleani true
e i false
Int16 valori.The following example converts the Boolean values true
and false
to Int16 values.
bool falseFlag = false;
bool trueFlag = true;
Console.WriteLine("{0} converts to {1}.", falseFlag,
Convert.ToInt16(falseFlag));
Console.WriteLine("{0} converts to {1}.", trueFlag,
Convert.ToInt16(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.ToInt16(falseFlag))
Console.WriteLine("{0} converts to {1}.", trueFlag, _
Convert.ToInt16(trueFlag))
' The example displays the following output:
' False converts to 0.
' True converts to 1.
Si applica a
ToInt16(Object)
Converte il valore dell'oggetto specificato in un intero con segno a 16 bit.Converts the value of the specified object to a 16-bit signed integer.
public:
static short ToInt16(System::Object ^ value);
public static short ToInt16 (object value);
static member ToInt16 : obj -> int16
Public Shared Function ToInt16 (value As Object) As Short
Parametri
- value
- Object
Oggetto che implementa l'interfaccia IConvertible oppure null
.An object that implements the IConvertible interface, or null
.
Restituisce
Intero con segno a 16 bit equivalente a value
oppure zero se value
è null
.A 16-bit signed integer that is equivalent to value
, or zero if value
is null
.
Eccezioni
Il formato di value
non è appropriato per un tipo Int16.value
is not in an appropriate format for an Int16 type.
value
non implementa l'interfaccia IConvertible.value
does not implement the IConvertible interface.
-oppure--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.
Esempio
Nell'esempio seguente si tenta di convertire ogni elemento in una matrice di oggetti in un intero con segno a 16 bit.The following example attempts to convert each element in an object array to a 16-bit signed integer.
object[] values= { true, -12, 163, 935, 'x', new DateTime(2009, 5, 12),
"104", "103.0", "-1", "1.00e2", "One", 1.00e2};
short result;
foreach (object value in values)
{
try {
result = Convert.ToInt16(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 Int16 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 Int16 exists for the {0} value {1}.",
value.GetType().Name, value);
}
}
// The example displays the following output:
// Converted the Boolean value True to the Int16 value 1.
// Converted the Int32 value -12 to the Int16 value -12.
// Converted the Int32 value 163 to the Int16 value 163.
// Converted the Int32 value 935 to the Int16 value 935.
// Converted the Char value x to the Int16 value 120.
// No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
// Converted the String value 104 to the Int16 value 104.
// The String value 103.0 is not in a recognizable format.
// Converted the String value -1 to the Int16 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 Int16 value 100.
Dim values() As Object = { True, -12, 163, 935, "x"c, #5/12/2009#, _
"104", "103.0", "-1", _
"1.00e2", "One", 1.00e2}
Dim result As Short
For Each value As Object In values
Try
result = Convert.ToInt16(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 Int16 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 Int16 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 Int16 value 1.
' Converted the Int32 value -12 to the Int16 value -12.
' Converted the Int32 value 163 to the Int16 value 163.
' Converted the Int32 value 935 to the Int16 value 935.
' Converted the Char value x to the Int16 value 120.
' No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
' Converted the String value 104 to the Int16 value 104.
' The String value 103.0 is not in a recognizable format.
' Converted the String value -1 to the Int16 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 Int16 value 100.
Commenti
Se value
non è null
, questo metodo esegue il wrapping di una chiamata all' IConvertible.ToInt16 implementazione del tipo sottostante di value
.If value
is not null
, this method wraps a call to the IConvertible.ToInt16 implementation of the underlying type of value
.