Enum.Parse Enum.Parse Enum.Parse Enum.Parse Method

定義

把一或多個列舉常數的名稱或數值的字串表示轉換為一個相等列舉物件。Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

多載

Parse(Type, String) Parse(Type, String) Parse(Type, String) Parse(Type, String)

把一或多個列舉常數的名稱或數值的字串表示轉換為一個相等列舉物件。Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

Parse(Type, String, Boolean) Parse(Type, String, Boolean) Parse(Type, String, Boolean) Parse(Type, String, Boolean)

把一或多個列舉常數的名稱或數值的字串表示轉換為一個相等列舉物件。Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. 參數會定義運算是否區分大小寫。A parameter specifies whether the operation is case-insensitive.

Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean)
Parse<TEnum>(String) Parse<TEnum>(String) Parse<TEnum>(String) Parse<TEnum>(String)

Parse(Type, String) Parse(Type, String) Parse(Type, String) Parse(Type, String)

把一或多個列舉常數的名稱或數值的字串表示轉換為一個相等列舉物件。Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object.

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value);
[System.Runtime.InteropServices.ComVisible(true)]
public static object Parse (Type enumType, string value);
static member Parse : Type * string -> obj
Public Shared Function Parse (enumType As Type, value As String) As Object

參數

enumType
Type Type Type Type

列舉類型。An enumeration type.

value
String String String String

字串,包含要轉換的名稱或數值。A string containing the name or value to convert.

傳回

enumType 類型的物件,其值以 value 表示。An object of type enumType whose value is represented by value.

例外狀況

enumTypevaluenullenumType or value is null.

enumType 不是 EnumenumType is not an Enum.

-或--or- value 為空字串 ("") 或只包含空格。value is either an empty string or only contains white space.

-或--or- value 為名稱,但不是為列舉所定義的其中一個具名常數。value is a name, but not one of the named constants defined for the enumeration.

value 超出 enumType 之基礎類型的範圍。value is outside the range of the underlying type of enumType.

範例

下列範例會使用Parse(Type, String)方法來剖析字串陣列,藉由呼叫GetNames方法。The following example uses the Parse(Type, String) method to parse an array of strings that are created by calling the GetNames method. 它也會使用Parse(Type, String)方法來剖析包含的位元欄位的列舉值。It also uses the Parse(Type, String) method to parse an enumeration value that consists of a bit field.

using namespace System;

[FlagsAttribute]
enum class Colors
{
   Red = 1,
   Green = 2,
   Blue = 4,
   Yellow = 8
};

int main()
{
   Console::WriteLine(  "The entries of the Colors enumeration are:" );
   Array^ a = Enum::GetNames( Colors::typeid );
   Int32 i = 0;
   while ( i < a->Length )
   {
      Object^ o = a->GetValue( i );
      Console::WriteLine( o->ToString() );
      i++;
   }

   Console::WriteLine();
   Object^ orange = Enum::Parse( Colors::typeid,  "Red, Yellow" );
   Console::WriteLine("The orange value has the combined entries of {0}", orange );
}

/*
This code example produces the following results:

The entries of the Colors Enum are:
Red
Green
Blue
Yellow

The orange value has the combined entries of Red, Yellow

*/
using System;

public class ParseTest
{
    [FlagsAttribute]
    enum Colors { Red = 1, Green = 2, Blue = 4, Yellow = 8 };

    public static void Main()
    {
        Console.WriteLine("The entries of the Colors enumeration are:");
        foreach (string colorName in Enum.GetNames(typeof(Colors)))
        {
            Console.WriteLine("{0} = {1:D}", colorName, 
                                         Enum.Parse(typeof(Colors), colorName));
        }
        Console.WriteLine();

        Colors orange = (Colors) Enum.Parse(typeof(Colors), "Red, Yellow");
        Console.WriteLine("The orange value {0:D} has the combined entries of {0}", 
                           orange);
    }
}

/*
This code example produces the following results:

The entries of the Colors Enum are:
Red = 1
Green = 2
Blue = 4
Yellow = 8

The orange value 9 has the combined entries of Red, Yellow

*/
Imports System

Public Class ParseTest

    <FlagsAttribute()> _
    Enum Colors
        Red = 1
        Green = 2
        Blue = 4
        Yellow = 8
    End Enum

    Public Shared Sub Main()
        Console.WriteLine("The entries of the Colors enumeration are:")
        Dim colorName As String
        For Each colorName In [Enum].GetNames(GetType(Colors))
            Console.WriteLine("{0} = {1:D}", colorName, [Enum].Parse(GetType(Colors), colorName))
        Next
        Console.WriteLine()

        Dim orange As Colors = CType([Enum].Parse(GetType(Colors), "Red, Yellow"), Colors)
        Console.WriteLine("The orange value {0:D} has the combined entries of {0}", orange)
    End Sub
End Class

'This example displays the following output:
'
'The entries of the Colors Enum are:
'Red = 1
'Green = 2
'Blue = 4
'Yellow = 8
'
'The myOrange value 9 has the combined entries of Red, Yellow
'

備註

value參數包含的字串表示法為列舉成員的基礎值或具名的常數,或一份名為以逗號 (,) 分隔的常數。The value parameter contains the string representation of an enumeration member's underlying value or named constant, or a list of named constants delimited by commas (,). 一或多個空格可以之前或之後每個值、 名稱或在逗號valueOne or more blank spaces can precede or follow each value, name, or comma in value. 如果value清單中,傳回的值是一個指定的名稱結合的位元值OR作業。If value is a list, the return value is the value of the specified names combined with a bitwise OR operation.

如果value是名稱未對應的具名常數enumType,方法會擲回ArgumentExceptionIf value is a name that does not correspond to a named constant of enumType, the method throws an ArgumentException. 如果value不代表基礎值的整數的字串表示法enumType列舉型別,此方法會傳回其基礎值是列舉成員value轉換成整數類資料類型。If value is the string representation of an integer that does not represent an underlying value of the enumType enumeration, the method returns an enumeration member whose underlying value is value converted to an integral type. 如果不需要此行為,呼叫IsDefined方法,以確保特定的字串表示的整數是實際的成員enumTypeIf this behavior is undesirable, call the IsDefined method to ensure that a particular string representation of an integer is actually a member of enumType. 下列範例會定義Colors列舉型別時,會呼叫Parse(Type, String)方法,以將字串轉換成其對應的列舉值,並呼叫IsDefined中值的方法,以確保特定的整數值為基礎Colors列舉型別。The following example defines a Colors enumeration, calls the Parse(Type, String) method to convert strings to their corresponding enumeration values, and calls the IsDefined method to ensure that particular integral values are underlying values in the Colors enumeration.

using System;

[Flags] enum Colors { None=0, Red = 1, Green = 2, Blue = 4 };
   
public class Example
{
   public static void Main()
   {
      string[] colorStrings = { "0", "2", "8", "blue", "Blue", "Yellow", "Red, Green" };
      foreach (string colorString in colorStrings)
      {
         try {
            Colors colorValue = (Colors) Enum.Parse(typeof(Colors), colorString);        
            if (Enum.IsDefined(typeof(Colors), colorValue) | colorValue.ToString().Contains(","))  
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString());
            else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString);
         }
         catch (ArgumentException) {
            Console.WriteLine("'{0}' is not a member of the Colors enumeration.", colorString);
         }
      }
   }
}
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       'blue' is not a member of the Colors enumeration.
//       Converted 'Blue' to Blue.
//       'Yellow' is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.
<Flags> Enum Colors As Integer
   None = 0
   Red = 1
   Green = 2
   Blue = 4
End Enum

Module Example
   Public Sub Main()
      Dim colorStrings() As String = {"0", "2", "8", "blue", "Blue", "Yellow", "Red, Green"}
      For Each colorString As String In colorStrings
         Try
            Dim colorValue As Colors = CType([Enum].Parse(GetType(Colors), colorString), Colors)        
            If [Enum].IsDefined(GetType(Colors), colorValue) Or colorValue.ToString().Contains(",") Then 
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString())
            Else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString)            
            End If                    
         Catch e As ArgumentException
            Console.WriteLine("'{0}' is not a member of the Colors enumeration.", colorString)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'       Converted '0' to None.
'       Converted '2' to Green.
'       8 is not an underlying value of the Colors enumeration.
'       'blue' is not a member of the Colors enumeration.
'       Converted 'Blue' to Blue.
'       'Yellow' is not a member of the Colors enumeration.
'       Converted 'Red, Green' to Red, Green.

這項作業會區分大小寫。This operation is case-sensitive.

另請參閱

Parse(Type, String, Boolean) Parse(Type, String, Boolean) Parse(Type, String, Boolean) Parse(Type, String, Boolean)

把一或多個列舉常數的名稱或數值的字串表示轉換為一個相等列舉物件。Converts the string representation of the name or numeric value of one or more enumerated constants to an equivalent enumerated object. 參數會定義運算是否區分大小寫。A parameter specifies whether the operation is case-insensitive.

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value, bool ignoreCase);
[System.Runtime.InteropServices.ComVisible(true)]
public static object Parse (Type enumType, string value, bool ignoreCase);
static member Parse : Type * string * bool -> obj
Public Shared Function Parse (enumType As Type, value As String, ignoreCase As Boolean) As Object

參數

enumType
Type Type Type Type

列舉類型。An enumeration type.

value
String String String String

字串,包含要轉換的名稱或數值。A string containing the name or value to convert.

ignoreCase
Boolean Boolean Boolean Boolean

true 表示忽略大小寫,false 表示區分大小寫。true to ignore case; false to regard case.

傳回

enumType 類型的物件,其值以 value 表示。An object of type enumType whose value is represented by value.

例外狀況

enumTypevaluenullenumType or value is null.

enumType 不是 EnumenumType is not an Enum.

-或--or- value 為空字串 ("") 或只包含空格。value is either an empty string ("") or only contains white space.

-或--or- value 為名稱,但不是為列舉所定義的其中一個具名常數。value is a name, but not one of the named constants defined for the enumeration.

value 超出 enumType 之基礎類型的範圍。value is outside the range of the underlying type of enumType.

範例

下列範例會使用Parse(Type, String, Boolean)方法來剖析字串陣列,藉由呼叫GetNames方法。The following example uses the Parse(Type, String, Boolean) method to parse an array of strings that are created by calling the GetNames method. 它也會使用Parse(Type, String)方法來剖析包含的位元欄位的列舉值。It also uses the Parse(Type, String) method to parse an enumeration value that consists of a bit field.

using System;

[Flags] enum Colors { None=0, Red = 1, Green = 2, Blue = 4 };
   
public class Example
{
   public static void Main()
   {
      string[] colorStrings = { "0", "2", "8", "blue", "Blue", "Yellow", "Red, Green" };
      foreach (string colorString in colorStrings)
      {
         try {
            Colors colorValue = (Colors) Enum.Parse(typeof(Colors), colorString, true);        
            if (Enum.IsDefined(typeof(Colors), colorValue) | colorValue.ToString().Contains(","))  
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString());
            else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString);
         }
         catch (ArgumentException) {
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString);
         }
      }
   }
}
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       Converted 'blue' to Blue.
//       Converted 'Blue' to Blue.
//       Yellow is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.
<Flags> Enum Colors As Integer
   None = 0
   Red = 1
   Green = 2
   Blue = 4
End Enum

Module Example
   Public Sub Main()
      Dim colorStrings() As String = {"0", "2", "8", "blue", "Blue", "Yellow", "Red, Green"}
      For Each colorString As String In colorStrings
         Try
            Dim colorValue As Colors = CType([Enum].Parse(GetType(Colors), colorString, True), Colors)        
            If [Enum].IsDefined(GetType(Colors), colorValue) Or colorValue.ToString().Contains(",") Then 
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString())
            Else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString)            
            End If                    
         Catch e As ArgumentException
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'       Converted '0' to None.
'       Converted '2' to Green.
'       8 is not an underlying value of the Colors enumeration.
'       Converted 'blue' to Blue.
'       Converted 'Blue' to Blue.
'       Yellow is not a member of the Colors enumeration.
'       Converted 'Red, Green' to Red, Green.

備註

value參數包含的字串表示法為列舉成員的基礎值或具名的常數,或一份名為以逗號 (,) 分隔的常數。The value parameter contains the string representation of an enumeration member's underlying value or named constant, or a list of named constants delimited by commas (,). 一或多個空格可以之前或之後每個值、 名稱或在逗號valueOne or more blank spaces can precede or follow each value, name, or comma in value. 如果value清單中,傳回的值是一個指定的名稱結合的位元值OR作業。If value is a list, the return value is the value of the specified names combined with a bitwise OR operation.

如果value是名稱未對應的具名常數enumType,方法會擲回ArgumentExceptionIf value is a name that does not correspond to a named constant of enumType, the method throws an ArgumentException. 如果value不代表基礎值的整數的字串表示法enumType列舉型別,此方法會傳回其基礎值是列舉成員value轉換成整數類資料類型。If value is the string representation of an integer that does not represent an underlying value of the enumType enumeration, the method returns an enumeration member whose underlying value is value converted to an integral type. 如果不需要此行為,呼叫IsDefined方法,以確保特定的字串表示的整數是實際的成員enumTypeIf this behavior is undesirable, call the IsDefined method to ensure that a particular string representation of an integer is actually a member of enumType. 下列範例會定義Colors列舉型別時,會呼叫Parse(Type, String, Boolean)方法,以將字串轉換成其對應的列舉值,並呼叫IsDefined中值的方法,以確保特定的整數值為基礎Colors列舉型別。The following example defines a Colors enumeration, calls the Parse(Type, String, Boolean) method to convert strings to their corresponding enumeration values, and calls the IsDefined method to ensure that particular integral values are underlying values in the Colors enumeration.

using System;

[Flags] enum Colors { None=0, Red = 1, Green = 2, Blue = 4 };
   
public class Example
{
   public static void Main()
   {
      string[] colorStrings = { "0", "2", "8", "blue", "Blue", "Yellow", "Red, Green" };
      foreach (string colorString in colorStrings)
      {
         try {
            Colors colorValue = (Colors) Enum.Parse(typeof(Colors), colorString, true);        
            if (Enum.IsDefined(typeof(Colors), colorValue) | colorValue.ToString().Contains(","))  
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString());
            else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString);
         }
         catch (ArgumentException) {
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString);
         }
      }
   }
}
// The example displays the following output:
//       Converted '0' to None.
//       Converted '2' to Green.
//       8 is not an underlying value of the Colors enumeration.
//       Converted 'blue' to Blue.
//       Converted 'Blue' to Blue.
//       Yellow is not a member of the Colors enumeration.
//       Converted 'Red, Green' to Red, Green.
<Flags> Enum Colors As Integer
   None = 0
   Red = 1
   Green = 2
   Blue = 4
End Enum

Module Example
   Public Sub Main()
      Dim colorStrings() As String = {"0", "2", "8", "blue", "Blue", "Yellow", "Red, Green"}
      For Each colorString As String In colorStrings
         Try
            Dim colorValue As Colors = CType([Enum].Parse(GetType(Colors), colorString, True), Colors)        
            If [Enum].IsDefined(GetType(Colors), colorValue) Or colorValue.ToString().Contains(",") Then 
               Console.WriteLine("Converted '{0}' to {1}.", colorString, colorValue.ToString())
            Else
               Console.WriteLine("{0} is not an underlying value of the Colors enumeration.", colorString)            
            End If                    
         Catch e As ArgumentException
            Console.WriteLine("{0} is not a member of the Colors enumeration.", colorString)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'       Converted '0' to None.
'       Converted '2' to Green.
'       8 is not an underlying value of the Colors enumeration.
'       Converted 'blue' to Blue.
'       Converted 'Blue' to Blue.
'       Yellow is not a member of the Colors enumeration.
'       Converted 'Red, Green' to Red, Green.

ignoreCase參數會指定這項作業是區分大小寫。The ignoreCase parameter specifies whether this operation is case-sensitive.

另請參閱

Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean) Parse<TEnum>(String, Boolean)

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(System::String ^ value, bool ignoreCase);
public static TEnum Parse<TEnum> (string value, bool ignoreCase) where TEnum : struct;
static member Parse : string * bool -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As String, ignoreCase As Boolean) As TEnum

類型參數

TEnum

參數

傳回

TEnum TEnum TEnum TEnum

Parse<TEnum>(String) Parse<TEnum>(String) Parse<TEnum>(String) Parse<TEnum>(String)

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(System::String ^ value);
public static TEnum Parse<TEnum> (string value) where TEnum : struct;
static member Parse : string -> 'Enum (requires 'Enum : struct)
Public Shared Function Parse(Of TEnum As Structure) (value As String) As TEnum

類型參數

TEnum

參數

傳回

TEnum TEnum TEnum TEnum

適用於