Enum.Parse 方法

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
 static System::Object ^ Parse(Type ^ enumType, ReadOnlySpan<char> value);

public static object Parse(Type enumType, ReadOnlySpan<char> value);

static member Parse : Type * ReadOnlySpan<char> -> obj

Public Shared Function Parse (enumType As Type, value As ReadOnlySpan(Of Char)) As Object

參數

傳回

一個型別 enumType 為 的物件，其值由 value表示。

例外狀況

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value);

public static object Parse(Type enumType, string value);

[System.Runtime.InteropServices.ComVisible(true)]
public static object Parse(Type enumType, string value);

static member Parse : Type * string -> obj

[<System.Runtime.InteropServices.ComVisible(true)>]
static member Parse : Type * string -> obj

Public Shared Function Parse (enumType As Type, value As String) As Object

參數

傳回

一個型別 enumType 為 的物件，其值由 value表示。

屬性

ComVisibleAttribute

例外狀況

範例

以下範例使用該 Parse(Type, String) 方法解析由呼叫 GetNames 該方法所建立的字串陣列。 它也使用該 Parse(Type, String) 方法解析由位元欄位組成的列舉值。

using System;

public class ParseTest
{
    [Flags]
    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

*/

open System

[<Flags>]
type Colors =
    | Red = 1
    | Green = 2
    | Blue = 4
    | Yellow = 8

printfn "The entries of the Colors enumeration are:"
for colorName in Enum.GetNames typeof<Colors> do
    printfn $"{colorName} = {Enum.Parse(typeof<Colors>, colorName):D}"
printfn ""

let orange = Enum.Parse(typeof<Colors>, "Red, Yellow") :?> Colors
printfn $"The orange value {orange:D} has the combined entries of {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

Public Class ParseTest

    <Flags()> _
    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

參數 value 包含列舉成員底層值或命名常數的字串表示，或以逗號（，）分隔的命名常數列表。 在 中，每個值、名稱或逗號 value前後都可以有一個或多個空白。 若 value 為列表，回傳值為指定名稱與位 OR 元運算的結合。

若 value 是不對應於 的 enumType命名常數的名稱，則該方法拋出一個 ArgumentException。 若 value 是整數的字串表示，且不代表列舉的 enumType 底層值，該方法會回傳一個枚舉成員，其底層值會 value 轉換為整數型別。 若此行為不理想，則呼叫該 IsDefined 方法以確保整數的特定字串表示實際上是 的成員 enumType。 以下範例定義列 Colors 舉，呼叫 Parse(Type, String) 將字串轉換為對應枚舉值的方法，並呼叫 IsDefined 該方法以確保特定整數值是枚舉的基礎值 Colors 。

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.

open System

[<Flags>]
type Colors =
    | None = 0
    | Red = 1
    | Green = 2
    | Blue = 4

let colorStrings = [ "0"; "2"; "8"; "blue"; "Blue"; "Yellow"; "Red, Green" ]
for colorString in colorStrings do
    try
        let colorValue = Enum.Parse(typeof<Colors>, colorString) :?> Colors
        if Enum.IsDefined(typeof<Colors>, colorValue) || (string colorValue).Contains "," then
            printfn $"Converted '{colorString}' to {colorValue}."
        else
            printfn $"{colorString} is not an underlying value of the Colors enumeration."
    with :? ArgumentException ->
        printfn $"'{colorString}' is not a member of the Colors enumeration."
// 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.

此作業區分大小寫。

另請參閱

• IsDefined(Type, Object)

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
 static System::Object ^ Parse(Type ^ enumType, ReadOnlySpan<char> value, bool ignoreCase);

public static object Parse(Type enumType, ReadOnlySpan<char> value, bool ignoreCase);

static member Parse : Type * ReadOnlySpan<char> * bool -> obj

Public Shared Function Parse (enumType As Type, value As ReadOnlySpan(Of Char), ignoreCase As Boolean) As Object

參數

傳回

一個型別 enumType 為 的物件，其值由 value表示。

例外狀況

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
 static System::Object ^ Parse(Type ^ enumType, System::String ^ value, bool ignoreCase);

public static object Parse(Type enumType, 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

[<System.Runtime.InteropServices.ComVisible(true)>]
static member Parse : Type * string * bool -> obj

Public Shared Function Parse (enumType As Type, value As String, ignoreCase As Boolean) As Object

參數

傳回

一個型別 enumType 為 的物件，其值由 value表示。

屬性

ComVisibleAttribute

例外狀況

範例

以下範例使用該 Parse(Type, String, Boolean) 方法解析由呼叫 GetNames 該方法所建立的字串陣列。 它也使用該 Parse(Type, String) 方法解析由位元欄位組成的列舉值。

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.

open System

[<Flags>]
type Colors =
    | None = 0
    | Red = 1
    | Green = 2
    | Blue = 4

let colorStrings = [ "0"; "2"; "8"; "blue"; "Blue"; "Yellow"; "Red, Green" ]
for colorString in colorStrings do
    try
        let colorValue = Enum.Parse(typeof<Colors>, colorString, true) :?> Colors
        if Enum.IsDefined(typeof<Colors>, colorValue) || (string colorValue).Contains "," then
            printfn $"Converted '{colorString}' to {colorValue}."
        else
            printfn $"{colorString} is not an underlying value of the Colors enumeration."
    with :? ArgumentException ->
        printfn $"{colorString} is not a member of the Colors enumeration."

// 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

參數 value 包含列舉成員底層值或命名常數的字串表示，或以逗號（，）分隔的命名常數列表。 在 中，每個值、名稱或逗號 value前後都可以有一個或多個空白。 若 value 為列表，回傳值為指定名稱與位 OR 元運算的結合。

若 value 是不對應於 的 enumType命名常數的名稱，則該方法拋出一個 ArgumentException。 若 value 是整數的字串表示，且不代表列舉的 enumType 底層值，該方法會回傳一個枚舉成員，其底層值會 value 轉換為整數型別。 若此行為不理想，則呼叫該 IsDefined 方法以確保整數的特定字串表示實際上是 的成員 enumType。 以下範例定義列 Colors 舉，呼叫 Parse(Type, String, Boolean) 將字串轉換為對應枚舉值的方法，並呼叫 IsDefined 該方法以確保特定整數值是枚舉的基礎值 Colors 。

參數 ignoreCase 指定此操作是否區分大小寫。

另請參閱

• IsDefined(Type, Object)

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

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

參數

傳回

一個型別 TEnum 為 的物件，其值由 value表示。

例外狀況

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(ReadOnlySpan<char> value, bool ignoreCase);

public static TEnum Parse<TEnum>(ReadOnlySpan<char> value, bool ignoreCase) where TEnum : struct;

static member Parse : ReadOnlySpan<char> * bool -> 'Enum (requires 'Enum : struct)

Public Shared Function Parse(Of TEnum As Structure) (value As ReadOnlySpan(Of Char), ignoreCase As Boolean) As TEnum

類型參數

參數

傳回

TEnum 一個型別 TEnum 為 的物件，其值由 value表示。

例外狀況

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

public:
generic <typename TEnum>
 where TEnum : value class static TEnum Parse(ReadOnlySpan<char> value);

public static TEnum Parse<TEnum>(ReadOnlySpan<char> value) where TEnum : struct;

static member Parse : ReadOnlySpan<char> -> 'Enum (requires 'Enum : struct)

Public Shared Function Parse(Of TEnum As Structure) (value As ReadOnlySpan(Of Char)) As TEnum

類型參數

參數

傳回

TEnum 一個型別 TEnum 為 的物件，其值由 value表示。

例外狀況

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

來源:

Enum.cs

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

參數

傳回

一個型別 TEnum 為 的物件，其值由 value表示。

例外狀況