Enum.GetNames 方法

定義

命名空間:

System

組件:

System.Runtime.dll

多載

GetNames(Type)	在指定的列舉中擷取常數名稱的陣列。
GetNames<TEnum>()	在指定的列舉類型中擷取常數名稱的陣列。

GetNames(Type)

Source:

Enum.cs

在指定的列舉中擷取常數名稱的陣列。

public:
 static cli::array <System::String ^> ^ GetNames(Type ^ enumType);

public static string[] GetNames (Type enumType);

static member GetNames : Type -> string[]

Public Shared Function GetNames (enumType As Type) As String()

參數

enumType

Type

列舉類型。

傳回

String[]

在 enumType 中的常數名稱字串陣列。

例外狀況

ArgumentNullException

enumType 為 null。

ArgumentException

enumType 參數不是 Enum。

InvalidOperationException

.NET 8 和更新版本： enumType 是布林值支援的列舉類型。

範例

在下列程式碼中，說明了如何使用 GetNames 方法。

using namespace System;
enum class Colors
{
   Red, Green, Blue, Yellow
};

enum class Styles
{
   Plaid, Striped, Tartan, Corduroy
};

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

   Console::WriteLine();
   Console::WriteLine( "The members of the Styles enum are:" );
   Array^ b = Enum::GetNames( Styles::typeid );
   i = 0;
   do
   {
      Object^ o = b->GetValue( i );
      Console::WriteLine( o->ToString() );
   }
   while ( ++i < b->Length );
}
// The example displays the following output:
//       The members of the Colors enum are:
//       Red
//       Green
//       Blue
//       Yellow
//       
//       The members of the Styles enum are:
//       Plaid
//       Striped
//       Tartan
//       Corduroy

using System;

public class GetNamesTest {
    enum Colors { Red, Green, Blue, Yellow };
    enum Styles { Plaid, Striped, Tartan, Corduroy };

    public static void Main() {

        Console.WriteLine("The members of the Colors enum are:");
        foreach(string s in Enum.GetNames(typeof(Colors)))
            Console.WriteLine(s);

        Console.WriteLine();

        Console.WriteLine("The members of the Styles enum are:");
        foreach(string s in Enum.GetNames(typeof(Styles)))
            Console.WriteLine(s);
    }
}
// The example displays the following output:
//       The members of the Colors enum are:
//       Red
//       Green
//       Blue
//       Yellow
//
//       The members of the Styles enum are:
//       Plaid
//       Striped
//       Tartan
//       Corduroy

open System

type Colors =
    | Red = 0
    | Green = 1
    | Blue = 2
    | Yellow = 3

type Styles =
    | Plaid = 0
    | Striped = 1
    | Tartan = 2
    | Corduroy = 3

printfn "The members of the Colors enum are:"
for s in Enum.GetNames typeof<Colors> do
    printfn $"{s}"

printfn "\nThe members of the Styles enum are:"
for s in Enum.GetNames typeof<Styles> do
    printfn $"{s}"
// The example displays the following output:
//       The members of the Colors enum are:
//       Red
//       Green
//       Blue
//       Yellow
//
//       The members of the Styles enum are:
//       Plaid
//       Striped
//       Tartan
//       Corduroy

Public Class GetNamesTest
    Enum Colors
        Red
        Green
        Blue
        Yellow
    End Enum 
    
    Enum Styles
        Plaid
        Striped
        Tartan
        Corduroy
    End Enum
    
    Public Shared Sub Main()
        
        Console.WriteLine("The members of the Colors enum are:")
        For Each s In [Enum].GetNames(GetType(Colors))
            Console.WriteLine(s)
        Next

        Console.WriteLine()
        
        Console.WriteLine("The members of the Styles enum are:")
        For Each s In [Enum].GetNames(GetType(Styles))
            Console.WriteLine(s)
        Next
    End Sub
End Class
' The example displays the following output:
'       The members of the Colors enum are:
'       Red
'       Green
'       Blue
'       Yellow
'       
'       The members of the Styles enum are:
'       Plaid
'       Striped
'       Tartan
'       Corduroy

備註

傳回值陣列的元素會依列舉常 (數的二進位值排序，也就是其不帶正負號的大小) 。 下列範例會針對包含負值、零和正值的列舉，提供 方法所 GetNames 傳回之陣列的相關資訊。

using System;

enum SignMagnitude { Negative = -1, Zero = 0, Positive = 1 };

public class Example
{
   public static void Main()
   {
      foreach (var name in Enum.GetNames(typeof(SignMagnitude))) {
         Console.WriteLine("{0,3:D}     0x{0:X}     {1}",
                           Enum.Parse(typeof(SignMagnitude), name),
                           name);
}   }
}
// The example displays the following output:
//         0     0x00000000     Zero
//         1     0x00000001     Positive
//        -1     0xFFFFFFFF     Negative

open System

type SignMagnitude =
   | Negative = -1
   | Zero = 0
   | Positive = 1

for name in Enum.GetNames typeof<SignMagnitude> do
    let p = Enum.Parse(typeof<SignMagnitude>, name)
    printfn $"{p,3:D}     0x{p:X}     {name}"

// The example displays the following output:
//         0     0x00000000     Zero
//         1     0x00000001     Positive
//        -1     0xFFFFFFFF     Negative

Public Enum SignMagnitude As Integer
   Negative = -1 
   Zero = 0
   Positive = 1
End Enum
   
Module Example
   Public Sub Main()
      Dim names() As String = [Enum].GetNames(GetType(SignMagnitude))
      For Each name In names
         Console.WriteLine("{0,3:D}     0x{0:X}     {1}", 
                           [Enum].Parse(GetType(SignMagnitude), name), 
                           name)
      Next
   End Sub
End Module
' The example displays the following output:
'      0     0x00000000     Zero
'      1     0x00000001     Positive
'     -1     0xFFFFFFFF     Negative

如果有具有相同值的列舉常數，則未指定其對應名稱的順序。

GetNames<TEnum>()

Source:

Enum.cs

在指定的列舉類型中擷取常數名稱的陣列。

public:
generic <typename TEnum>
 where TEnum : value class static cli::array <System::String ^> ^ GetNames();

public static string[] GetNames<TEnum> () where TEnum : struct;

static member GetNames : unit -> string[] (requires 'Enum : struct)

Public Shared Function GetNames(Of TEnum As Structure) () As String()

類型參數

TEnum

列舉的型別。

傳回

String[]

在 TEnum 中的常數名稱字串陣列。

例外狀況

InvalidOperationException

.NET 8 和更新版本： TEnum 是布林值支援的列舉類型。