FieldBuilder.Attributes Property

Definition

Namespace:

System.Reflection.Emit

Assembly:

System.Reflection.Emit.dll

Indicates the attributes of this field. This property is read-only.

public:
 virtual property System::Reflection::FieldAttributes Attributes { System::Reflection::FieldAttributes get(); };

public override System.Reflection.FieldAttributes Attributes { get; }

member this.Attributes : System.Reflection.FieldAttributes

Public Overrides ReadOnly Property Attributes As FieldAttributes

Property Value

FieldAttributes

The attributes of this field.

Remarks

The following code sample illustrates the use of Attributes.

using namespace System;
using namespace System::Threading;
using namespace System::Reflection;
using namespace System::Reflection::Emit;
Type^ CreateType( AppDomain^ currentDomain )
{
   // Create an assembly.
   AssemblyName^ myAssemblyName = gcnew AssemblyName;
   myAssemblyName->Name = "DynamicAssembly";
   AssemblyBuilder^ myAssembly = currentDomain->DefineDynamicAssembly( myAssemblyName, AssemblyBuilderAccess::Run );

   // Create a dynamic module in Dynamic Assembly.
   ModuleBuilder^ myModuleBuilder = myAssembly->DefineDynamicModule( "MyModule" );

   // Define a public class named S"MyClass" in the assembly.
   TypeBuilder^ myTypeBuilder = myModuleBuilder->DefineType( "MyClass", TypeAttributes::Public );

   // Define a private String field named S"MyField" in the type.
   FieldBuilder^ myFieldBuilder = myTypeBuilder->DefineField( "MyField", String::typeid, static_cast<FieldAttributes>(FieldAttributes::Private | FieldAttributes::Static) );

   // Create the constructor.
   array<Type^>^constructorArgs = {String::typeid};
   ConstructorBuilder^ myConstructor = myTypeBuilder->DefineConstructor( MethodAttributes::Public, CallingConventions::Standard, constructorArgs );
   ILGenerator^ constructorIL = myConstructor->GetILGenerator();
   constructorIL->Emit( OpCodes::Ldarg_0 );
   ConstructorInfo^ superConstructor = Object::typeid->GetConstructor( gcnew array<Type^>(0) );
   constructorIL->Emit( OpCodes::Call, superConstructor );
   constructorIL->Emit( OpCodes::Ldarg_0 );
   constructorIL->Emit( OpCodes::Ldarg_1 );
   constructorIL->Emit( OpCodes::Stfld, myFieldBuilder );
   constructorIL->Emit( OpCodes::Ret );

   // Create the MyMethod method.
   MethodBuilder^ myMethodBuilder = myTypeBuilder->DefineMethod( "MyMethod", MethodAttributes::Public, String::typeid, nullptr );
   ILGenerator^ methodIL = myMethodBuilder->GetILGenerator();
   methodIL->Emit( OpCodes::Ldarg_0 );
   methodIL->Emit( OpCodes::Ldfld, myFieldBuilder );
   methodIL->Emit( OpCodes::Ret );
   if ( myFieldBuilder->Attributes.Equals( FieldAttributes::Static ) )
   {
      Console::WriteLine( "Field attribute defined as Static" );
   }
   else
   if ( myFieldBuilder->Attributes.Equals( FieldAttributes::Static | FieldAttributes::Private ) )
   {
      Console::WriteLine( "Field attributes are Static and Private" );
   }


   Console::WriteLine( "ReflectedType of Field is : {0}", myFieldBuilder->ReflectedType );
   return myTypeBuilder->CreateType();
}

int main()
{
   try
   {
      Type^ myType = CreateType( Thread::GetDomain() );

      // Create an instance of the S"HelloWorld" class.
      array<Object^>^type = {"HelloWorld"};
      Object^ helloWorld = Activator::CreateInstance( myType, type );

      // Invoke the S"MyMethod"  of the S"MyClass".
      Object^ myObject = myType->InvokeMember( "MyMethod", BindingFlags::InvokeMethod, nullptr, helloWorld, nullptr );
      Console::WriteLine( "MyClass::MyMethod returned: \"{0}\"", myObject );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Exception Caught {0}", e->Message );
   }
}

using System;
using System.Threading;
using System.Reflection;
using System.Reflection.Emit;
using System.Security.Permissions;

public class FieldBuilder_Sample
{
   private static Type CreateType(AppDomain currentDomain)
   {

      // Create an assembly.
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "DynamicAssembly";
      AssemblyBuilder myAssembly =
         currentDomain.DefineDynamicAssembly(myAssemblyName,AssemblyBuilderAccess.Run);
      // Create a dynamic module in Dynamic Assembly.
      ModuleBuilder myModuleBuilder=myAssembly.DefineDynamicModule("MyModule");
      // Define a public class named "MyClass" in the assembly.
      TypeBuilder myTypeBuilder= myModuleBuilder.DefineType("MyClass",TypeAttributes.Public);

      // Define a private String field named "MyField" in the type.
      FieldBuilder myFieldBuilder= myTypeBuilder.DefineField("MyField",
         typeof(string),FieldAttributes.Private|FieldAttributes.Static);
      // Create the constructor.
      Type[] constructorArgs = { typeof(String) };
      ConstructorBuilder myConstructor = myTypeBuilder.DefineConstructor(
         MethodAttributes.Public, CallingConventions.Standard, constructorArgs);
      ILGenerator constructorIL = myConstructor.GetILGenerator();
      constructorIL.Emit(OpCodes.Ldarg_0);
      ConstructorInfo superConstructor = typeof(Object).GetConstructor(new Type[0]);
      constructorIL.Emit(OpCodes.Call, superConstructor);
      constructorIL.Emit(OpCodes.Ldarg_0);
      constructorIL.Emit(OpCodes.Ldarg_1);
      constructorIL.Emit(OpCodes.Stfld, myFieldBuilder);
      constructorIL.Emit(OpCodes.Ret);

      // Create the MyMethod method.
      MethodBuilder myMethodBuilder= myTypeBuilder.DefineMethod("MyMethod",
         MethodAttributes.Public,typeof(String),null);
      ILGenerator methodIL = myMethodBuilder.GetILGenerator();
      methodIL.Emit(OpCodes.Ldarg_0);
      methodIL.Emit(OpCodes.Ldfld, myFieldBuilder);
      methodIL.Emit(OpCodes.Ret);
      if (myFieldBuilder.Attributes.Equals(FieldAttributes.Static))
      {
            Console.WriteLine("Field attribute defined as Static");
      }
      else if(myFieldBuilder.Attributes.Equals(FieldAttributes.Static|FieldAttributes.Private))
      {
         Console.WriteLine("Field attributes are Static and Private");
      }
      Console.WriteLine("ReflectedType of Field is: " + myFieldBuilder.ReflectedType);

      return myTypeBuilder.CreateType();
   }

   public static void Main()
   {
      Type myType = CreateType(Thread.GetDomain());
      // Create an instance of the "HelloWorld" class.
      Object helloWorld = Activator.CreateInstance(myType, new Object[] { "HelloWorld" });
      // Invoke the "MyMethod"  of the "MyClass".
      Object myObject  = myType.InvokeMember("MyMethod",
         BindingFlags.InvokeMethod, null, helloWorld, null);
      Console.WriteLine("MyClass.MyMethod returned: \"" + myObject + "\"");
   }
}

Imports System.Threading
Imports System.Reflection
Imports System.Reflection.Emit
Imports System.Security.Permissions

Public Class FieldBuilder_Sample
   Private Shared Function CreateType(currentDomain As AppDomain) As Type

      ' Create an assembly.
      Dim myAssemblyName As New AssemblyName()
      myAssemblyName.Name = "DynamicAssembly"
      Dim myAssembly As AssemblyBuilder = currentDomain.DefineDynamicAssembly(myAssemblyName, _
                                             AssemblyBuilderAccess.Run)
      ' Create a dynamic module in Dynamic Assembly.
      Dim myModuleBuilder As ModuleBuilder = myAssembly.DefineDynamicModule("MyModule")
      ' Define a public class named "MyClass" in the assembly.
      Dim myTypeBuilder As TypeBuilder = myModuleBuilder.DefineType("MyClass", _
                                          TypeAttributes.Public)
      ' Define a private String field named "MyField" in the type.
      Dim myFieldBuilder As FieldBuilder = myTypeBuilder.DefineField("MyField", _
                              GetType(String), FieldAttributes.Private Or FieldAttributes.Static)
      ' Create the constructor.
      Dim constructorArgs As Type() ={GetType(String)}
      Dim myConstructor As ConstructorBuilder = _
                     myTypeBuilder.DefineConstructor(MethodAttributes.Public, _
                              CallingConventions.Standard, constructorArgs)
      Dim constructorIL As ILGenerator = myConstructor.GetILGenerator()
      constructorIL.Emit(OpCodes.Ldarg_0)
      Dim superConstructor As ConstructorInfo = GetType(Object).GetConstructor(New Type() { })
      constructorIL.Emit(OpCodes.Call, superConstructor)
      constructorIL.Emit(OpCodes.Ldarg_0)
      constructorIL.Emit(OpCodes.Ldarg_1)
      constructorIL.Emit(OpCodes.Stfld, myFieldBuilder)
      constructorIL.Emit(OpCodes.Ret)
      
      ' Create the MyMethod method.
      Dim myMethodBuilder As MethodBuilder =myTypeBuilder.DefineMethod("MyMethod", _
                           MethodAttributes.Public, GetType(String), Nothing)
      Dim methodIL As ILGenerator = myMethodBuilder.GetILGenerator()
      methodIL.Emit(OpCodes.Ldarg_0)
      methodIL.Emit(OpCodes.Ldfld, myFieldBuilder)
      methodIL.Emit(OpCodes.Ret)
      If myFieldBuilder.Attributes.Equals(FieldAttributes.Static) Then
         Console.WriteLine("Field attribute defined as Static")
      Else
         If myFieldBuilder.Attributes.Equals(FieldAttributes.Static Or FieldAttributes.Private) Then
            Console.WriteLine("Field attributes are Static and Private")
         End If
      End If
      Console.WriteLine("ReflectedType of Field is: " & myFieldBuilder.ReflectedType.ToString())
      Return myTypeBuilder.CreateType()

   End Function 'CreateType

   <PermissionSetAttribute(SecurityAction.Demand, Name:="FullTrust")> _
   Public Shared Sub Main()
      Dim myType As Type = CreateType(Thread.GetDomain())
      ' Create an instance of the "HelloWorld" class.
      Dim helloWorld As Object = Activator.CreateInstance(myType, New Object() { "HelloWorld" })
      ' Invoke the "MyMethod"  of the "MyClass".
      Dim myObject As Object = myType.InvokeMember("MyMethod", _
               BindingFlags.InvokeMethod, Nothing, helloWorld, Nothing)
      Console.WriteLine("MyClass.MyMethod returned: """ & myObject & """")
   End Sub
End Class