EnumBuilder.DefineLiteral(String, Object) Método

Definição

Namespace:

System.Reflection.Emit

Assembly:

System.Reflection.Emit.dll

Origem:

EnumBuilder.cs

Define o campo estático chamado em um tipo de enumeração com o valor constante especificado.

public:
 System::Reflection::Emit::FieldBuilder ^ DefineLiteral(System::String ^ literalName, System::Object ^ literalValue);

public System.Reflection.Emit.FieldBuilder DefineLiteral (string literalName, object? literalValue);

member this.DefineLiteral : string * obj -> System.Reflection.Emit.FieldBuilder

Public Function DefineLiteral (literalName As String, literalValue As Object) As FieldBuilder

Parâmetros

literalName

String

O nome do campo estático.

literalValue

Object

O valor constante do literal.

Retornos

FieldBuilder

O campo definido.

Exemplos

O exemplo de código a seguir demonstra a construção de uma enumeração em um assembly dinâmico, usando EnumBuilder. O exemplo define uma enumeração chamada Elevation, com um tipo subjacente de Int32e cria dois elementos: Low, com um valor de 0 e High, com um valor de 1. Depois que o tipo for criado, o assembly será salvo com o nome TempAssembly.dll. Você pode usar o Ildasm.exe (Il Disassembler) para examinar o conteúdo deste assembly.

Observação

Antes do .NET Framework versão 2.0, este exemplo de código não produz uma enumeração correta.

using namespace System;
using namespace System::Reflection;
using namespace System::Reflection::Emit;

void main()
{
    // Get the current application domain for the current thread.
    AppDomain^ currentDomain = AppDomain::CurrentDomain;
      
    // Create a dynamic assembly in the current application domain, 
    // and allow it to be executed and saved to disk.
    AssemblyName^ aName = gcnew AssemblyName("TempAssembly");
    AssemblyBuilder^ ab = currentDomain->DefineDynamicAssembly( 
            aName, AssemblyBuilderAccess::RunAndSave);
      
    // Define a dynamic module in "TempAssembly" assembly. For a single-
    // module assembly, the module has the same name as the assembly.
    ModuleBuilder^ mb = 
            ab->DefineDynamicModule(aName->Name, aName->Name + ".dll");
      
    // Define a public enumeration with the name "Elevation" and an 
    // underlying type of Int32.
    EnumBuilder^ eb = 
            mb->DefineEnum("Elevation", TypeAttributes::Public, int::typeid);
      
    // Define two members, "High" and "Low".
    eb->DefineLiteral("Low", (Object^) 0);
    eb->DefineLiteral("High", 1);

    // Create the type and save the assembly.
    Type^ finished = eb->CreateType();
    ab->Save(aName->Name + ".dll");

    for each (Object^ o in Enum::GetValues(finished))
    {
        Console::WriteLine("{0}.{1} = {2}", finished, o, (int)o);
    }
}

/* This code example produces the following output:

Elevation.Low = 0
Elevation.High = 1
 */

using System;
using System.Reflection;
using System.Reflection.Emit;

class Example
{
    public static void Main()
    {
        // Get the current application domain for the current thread.
        AppDomain currentDomain = AppDomain.CurrentDomain;

        // Create a dynamic assembly in the current application domain,
        // and allow it to be executed and saved to disk.
        AssemblyName aName = new AssemblyName("TempAssembly");
        AssemblyBuilder ab = currentDomain.DefineDynamicAssembly(
            aName, AssemblyBuilderAccess.RunAndSave);

        // Define a dynamic module in "TempAssembly" assembly. For a single-
        // module assembly, the module has the same name as the assembly.
        ModuleBuilder mb = ab.DefineDynamicModule(aName.Name, aName.Name + ".dll");

        // Define a public enumeration with the name "Elevation" and an
        // underlying type of Integer.
        EnumBuilder eb = mb.DefineEnum("Elevation", TypeAttributes.Public, typeof(int));

        // Define two members, "High" and "Low".
        eb.DefineLiteral("Low", 0);
        eb.DefineLiteral("High", 1);

        // Create the type and save the assembly.
        Type finished = eb.CreateType();
        ab.Save(aName.Name + ".dll");

        foreach( object o in Enum.GetValues(finished) )
        {
            Console.WriteLine("{0}.{1} = {2}", finished, o, ((int) o));
        }
    }
}

/* This code example produces the following output:

Elevation.Low = 0
Elevation.High = 1
 */

Imports System.Reflection
Imports System.Reflection.Emit

Module Example
   
    Sub Main()
      
        ' Get the current application domain for the current thread.
        Dim currentDomain As AppDomain = AppDomain.CurrentDomain
      
        ' Create a dynamic assembly in the current application domain, 
        ' and allow it to be executed and saved to disk.
        Dim aName As AssemblyName = New AssemblyName("TempAssembly")
        Dim ab As AssemblyBuilder = currentDomain.DefineDynamicAssembly( _ 
            aName, AssemblyBuilderAccess.RunAndSave)
      
        ' Define a dynamic module in "TempAssembly" assembly. For a single-
        ' module assembly, the module has the same name as the assembly.
        Dim mb As ModuleBuilder = _
            ab.DefineDynamicModule(aName.Name, aName.Name & ".dll")
      
        ' Define a public enumeration with the name "Elevation" and an 
        ' underlying type of Integer.
        Dim eb As EnumBuilder = _
            mb.DefineEnum("Elevation", TypeAttributes.Public, GetType(Integer))
      
        ' Define two members, "High" and "Low".
        eb.DefineLiteral("Low", 0)
        eb.DefineLiteral("High", 1)

        ' Create the type and save the assembly.
        Dim finished As Type = eb.CreateType()
        ab.Save(aName.Name & ".dll")

        For Each o As Object In [Enum].GetValues(finished)
            Console.WriteLine("{0}.{1} = {2}", finished, o, CInt(o))
        Next
   End Sub
End Module

' This code example produces the following output:
'
'Elevation.Low = 0
'Elevation.High = 1

Comentários

O campo definido terá os atributos Publicde campo , Statice Literal definidos.

Observação

No .NET Framework versões 1.0 e 1.1, é necessário definir enumerações usando TypeBuilder porque EnumBuilder emite enumerações cujos elementos são do tipo Int32 em vez do tipo de enumeração. No .NET Framework versão 2.0, EnumBuilder emite enumerações cujos elementos têm o tipo correto.