แก้ไข

แชร์ผ่าน


Enum.GetValues Method

Definition

Overloads

GetValues(Type)

Retrieves an array of the values of the constants in a specified enumeration.

GetValues<TEnum>()

Retrieves an array of the values of the constants in a specified enumeration type.

GetValues(Type)

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Retrieves an array of the values of the constants in a specified enumeration.

public:
 static Array ^ GetValues(Type ^ enumType);
public static Array GetValues (Type enumType);
[System.Runtime.InteropServices.ComVisible(true)]
public static Array GetValues (Type enumType);
static member GetValues : Type -> Array
[<System.Runtime.InteropServices.ComVisible(true)>]
static member GetValues : Type -> Array
Public Shared Function GetValues (enumType As Type) As Array

Parameters

enumType
Type

An enumeration type.

Returns

An array that contains the values of the constants in enumType.

Attributes

Exceptions

enumType is null.

enumType is not an Enum.

The method is invoked by reflection in a reflection-only context,

-or-

enumType is a type from an assembly loaded in a reflection-only context.

.NET 8 and later versions: enumType is a Boolean-backed enumeration type.

Examples

The following example illustrates the use of GetValues.

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

enum class Styles
{
   Plaid = 0,
   Striped = 23,
   Tartan = 65,
   Corduroy = 78
};

int main()
{
   Console::WriteLine(  "The values of the Colors Enum are:" );
   Array^ a = Enum::GetValues( Colors::typeid );
   for ( Int32 i = 0; i < a->Length; i++ )
   {
      Object^ o = a->GetValue( i );
      Console::WriteLine(  "{0}", Enum::Format( Colors::typeid, o,  "D" ) );
   }
   Console::WriteLine();
   Console::WriteLine(  "The values of the Styles Enum are:" );
   Array^ b = Enum::GetValues( Styles::typeid );
   for ( Int32 i = 0; i < b->Length; i++ )
   {
      Object^ o = b->GetValue( i );
      Console::WriteLine(  "{0}", Enum::Format( Styles::typeid, o,  "D" ) );

   }
}
// The example produces the following output:
//       The values of the Colors Enum are:
//       0
//       1
//       2
//       3
//       
//       The values of the Styles Enum are:
//       0
//       23
//       65
//       78
using System;

public class GetValuesTest {
    enum Colors { Red, Green, Blue, Yellow };
    enum Styles { Plaid = 0, Striped = 23, Tartan = 65, Corduroy = 78 };

    public static void Main() {

        Console.WriteLine("The values of the Colors Enum are:");
        foreach(int i in Enum.GetValues(typeof(Colors)))
            Console.WriteLine(i);

        Console.WriteLine();

        Console.WriteLine("The values of the Styles Enum are:");
        foreach(int i in Enum.GetValues(typeof(Styles)))
            Console.WriteLine(i);
    }
}
// The example produces the following output:
//       The values of the Colors Enum are:
//       0
//       1
//       2
//       3
//
//       The values of the Styles Enum are:
//       0
//       23
//       65
//       78
open System

type Colors =
    | Red = 0
    | Green = 1
    | Blue = 2
    | Yellow = 3
    
type Styles =
    | Plaid = 0
    | Striped = 23
    | Tartan = 65
    | Corduroy = 78

printfn $"The values of the Colors Enum are:"
for i in Enum.GetValues typeof<Colors> do
    printfn $"{i}"

printfn "\nThe values of the Styles Enum are:"
for i in Enum.GetValues typeof<Styles> do
    printfn $"{i}"

// The example produces the following output:
//       The values of the Colors Enum are:
//       0
//       1
//       2
//       3
//
//       The values of the Styles Enum are:
//       0
//       23
//       65
//       78
Public Class GetValuesTest
   
    Enum Colors
        Red
        Green
        Blue
        Yellow
    End Enum 'Colors
    
    Enum Styles
        Plaid = 0
        Striped = 23
        Tartan = 65
        Corduroy = 78
    End Enum 'Styles
    
    Public Shared Sub Main()
        
        Console.WriteLine("The values of the Colors Enum are:")
        Dim i As Integer
        For Each i In  [Enum].GetValues(GetType(Colors))
            Console.WriteLine(i)
        Next

        Console.WriteLine()
        
        Console.WriteLine("The values of the Styles Enum are:")
        For Each i In  [Enum].GetValues(GetType(Styles))
            Console.WriteLine(i)
        Next
    End Sub 
End Class 
' The example produces the following output:
'       The values of the Colors Enum are:
'       0
'       1
'       2
'       3
'       
'       The values of the Styles Enum are:
'       0
'       23
'       65
'       78

Remarks

The elements of the array are sorted by the binary values of the enumeration constants (that is, by their unsigned magnitude). The following example displays information about the array returned by the GetValues method for an enumeration that includes a negative value, zero, and a positive value.

using System;

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

public class Example
{
   public static void Main()
   {
      foreach (var value in Enum.GetValues(typeof(SignMagnitude))) {
         Console.WriteLine("{0,3}     0x{0:X8}     {1}",
                           (int) value, ((SignMagnitude) value));
}   }
}
// 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 value in Enum.GetValues typeof<SignMagnitude> do
    printfn $"{value :?> int,3}     0x{value :?> int:X8}     {value :?> SignMagnitude}"
// 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 values() As Integer = CType([Enum].GetValues(GetType(SignMagnitude)), Integer())
      For Each value In values
         Console.WriteLine("{0,3}     0x{0:X8}     {1}",
                           value, CType(value, SignMagnitude).ToString())
      Next
   End Sub
End Module
' The example displays the following output:
'      0     0x00000000     Zero
'      1     0x00000001     Positive
'     -1     0xFFFFFFFF     Negative

The GetValues method returns an array that contains a value for each member of the enumType enumeration. If multiple members have the same value, the returned array includes duplicate values. In this case, calling the GetName method with each value in the returned array does not restore the unique names assigned to members that have duplicate values. To retrieve all the names of enumeration members successfully, call the GetNames method.

The GetValues method cannot be invoked by using reflection in a reflection-only context. Instead, you can retrieve the value of all enumeration members by using the Type.GetFields method to get an array of FieldInfo objects that represent enumeration members and then call the FieldInfo.GetRawConstantValue method on each element of the array. The following example illustrates this technique. It requires that you define the following enumeration in an assembly named Enumerations.dll:

[Flags] enum Pets { None=0, Dog=1, Cat=2, Rodent=4, Bird=8,
                    Fish=16, Reptile=32, Other=64 };
[<Flags>] 
type Pets =
    | None = 0
    | Dog = 1
    | Cat = 2
    | Rodent = 4
    | Bird = 8
    | Fish = 16
    | Reptile = 32
    | Other = 64
<Flags> Public Enum Pets As Integer
   None = 0
   Dog = 1
   Cat = 2
   Rodent = 4
   Bird = 8
   Fish = 16
   Reptile = 32
   Other = 64
End Enum

The assembly is loaded in a reflection-only context, a Type object that represents the Pets enumeration is instantiated, an array of FieldInfo objects is retrieved, and the field values are displayed to the console.

using System;
using System.Reflection;

public class Example
{
   public static void Main()
   {
      Assembly assem = Assembly.ReflectionOnlyLoadFrom(@".\Enumerations.dll");
      Type typ = assem.GetType("Pets");
      FieldInfo[] fields = typ.GetFields();

      foreach (var field in fields) {
         if (field.Name.Equals("value__")) continue;

         Console.WriteLine("{0,-9} {1}", field.Name + ":",
                                         field.GetRawConstantValue());
      }
   }
}
// The example displays the following output:
//       None:     0
//       Dog:      1
//       Cat:      2
//       Rodent:   4
//       Bird:     8
//       Fish:     16
//       Reptile:  32
//       Other:    64
open System
open System.Reflection

let assem = Assembly.ReflectionOnlyLoadFrom @".\Enumerations.dll"
let typ = assem.GetType "Pets"
let fields = typ.GetFields()

for field in fields do
    if not (field.Name.Equals "value__") then

        printfn $"""{field.Name + ":",-9} {field.GetRawConstantValue()}"""
// The example displays the following output:
//       None:     0
//       Dog:      1
//       Cat:      2
//       Rodent:   4
//       Bird:     8
//       Fish:     16
//       Reptile:  32
//       Other:    64
Imports System.Reflection

Module Example
   Public Sub Main()
      Dim assem As Assembly = Assembly.ReflectionOnlyLoadFrom(".\Enumerations.dll")
      Dim typ As Type = assem.GetType("Pets")
      Dim fields As FieldInfo() = typ.GetFields

      For Each field In fields
         If field.Name.Equals("value__") Then Continue For
          
         Console.WriteLine("{0,-9} {1}", field.Name + ":", 
                                         field.GetRawConstantValue())
      Next
   End Sub
End Module
' The example displays the following output:
'       None:     0
'       Dog:      1
'       Cat:      2
'       Rodent:   4
'       Bird:     8
'       Fish:     16
'       Reptile:  32
'       Other:    64

Applies to

GetValues<TEnum>()

Source:
Enum.cs
Source:
Enum.cs
Source:
Enum.cs

Retrieves an array of the values of the constants in a specified enumeration type.

public:
generic <typename TEnum>
 where TEnum : value class static cli::array <TEnum> ^ GetValues();
public static TEnum[] GetValues<TEnum> () where TEnum : struct;
static member GetValues : unit -> 'Enum[] (requires 'Enum : struct)
Public Shared Function GetValues(Of TEnum As Structure) () As TEnum()

Type Parameters

TEnum

The type of the enumeration.

Returns

TEnum[]

An array that contains the values of the constants in TEnum.

Exceptions

.NET 8 and later versions: TEnum is a Boolean-backed enumeration type.

Applies to