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Enum.GetNames Method

  • Reference

Definition

Namespace:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll

Overloads

GetNames(Type)

Retrieves an array of the names of the constants in a specified enumeration.
GetNames<TEnum>()

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

GetNames(Type)

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

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

public:
 static cli::array <System::String ^> ^ GetNames(Type ^ enumType);
public static string[] GetNames (Type enumType);
[System.Runtime.InteropServices.ComVisible(true)]
public static string[] GetNames (Type enumType);
static member GetNames : Type -> string[]
[<System.Runtime.InteropServices.ComVisible(true)>]
static member GetNames : Type -> string[]
Public Shared Function GetNames (enumType As Type) As String()

Parameters

enumType
Type

An enumeration type.

Returns

String[]

A string array of the names of the constants in enumType.

Attributes
ComVisibleAttribute

Exceptions

ArgumentNullException

enumType is null.

ArgumentException

enumType parameter is not an Enum.

InvalidOperationException

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

Examples

The following example illustrates the use of the GetNames method.

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

Remarks

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

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

If there are enumerated constants with same value, the order of their corresponding names is unspecified.

Applies to

GetNames<TEnum>()

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

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

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()

Type Parameters

TEnum

The type of the enumeration.

Returns

String[]

A string array of the names of the constants in TEnum.

Exceptions

InvalidOperationException

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

Applies to