TypeBuilder.DefineMethod Method (String, MethodAttributes, Type, Type[])

 
System_CAPS_noteNote

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Adds a new method to the type, with the specified name, method attributes, and method signature.

Namespace:   System.Reflection.Emit
Assembly:  mscorlib (in mscorlib.dll)

public MethodBuilder DefineMethod(
	string name,
	MethodAttributes attributes,
	Type returnType,
	Type[] parameterTypes
)

Parameters

name
Type: System.String

The name of the method. name cannot contain embedded nulls.

attributes
Type: System.Reflection.MethodAttributes

The attributes of the method.

returnType
Type: System.Type

The return type of the method.

parameterTypes
Type: System.Type[]

The types of the parameters of the method.

Return Value

Type: System.Reflection.Emit.MethodBuilder

The defined method.

Exception Condition
ArgumentException

The length of name is zero.

-or-

The type of the parent of this method is an interface, and this method is not virtual (Overridable in Visual Basic).

ArgumentNullException

name is null.

InvalidOperationException

The type was previously created using CreateType.

-or-

For the current dynamic type, the IsGenericType property is true, but the IsGenericTypeDefinition property is false.

The following code sample demonstrates the use of DefineMethod to set a constructor's particular signature and attributes on a dynamic type and to return a corresponding MethodBuilder for MSIL population.

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

public interface IMyInterface
{
   String HelloMethod(String parameter);
}

public class Example
{
   [PermissionSetAttribute(SecurityAction.Demand, Name="FullTrust")]
   public static void Main()
   {
      Type myNestedClassType = CreateCallee(Thread.GetDomain());
      // Cretae an instance of 'MyNestedClass'.
      IMyInterface myInterface =
         (IMyInterface)Activator.CreateInstance(myNestedClassType);
      Console.WriteLine(myInterface.HelloMethod("Bill"));
   }

   // Create the callee transient dynamic assembly.
   private static Type CreateCallee(AppDomain myAppDomain)
   {
      AssemblyName myAssemblyName = new AssemblyName();
      myAssemblyName.Name = "Example";
      // Create the callee dynamic assembly.
      AssemblyBuilder myAssembly =
         myAppDomain.DefineDynamicAssembly(myAssemblyName, AssemblyBuilderAccess.Run);
      // Create a dynamic module in the callee assembly.
      ModuleBuilder myModule = myAssembly.DefineDynamicModule("EmittedModule");
      // Define a public class named "MyHelloWorld".
      TypeBuilder myHelloWorldType =
         myModule.DefineType("MyHelloWorld", TypeAttributes.Public);
      // Define a public nested class named 'MyNestedClass'.
      TypeBuilder myNestedClassType =
         myHelloWorldType.DefineNestedType("MyNestedClass",
            TypeAttributes.NestedPublic, typeof(Example),
            new Type[]{typeof(IMyInterface)});
      // Implement 'IMyInterface' interface.
      myNestedClassType.AddInterfaceImplementation(typeof(IMyInterface));
      // Define 'HelloMethod' of 'IMyInterface'.
      MethodBuilder myHelloMethod =
         myNestedClassType.DefineMethod("HelloMethod",
            MethodAttributes.Public | MethodAttributes.Virtual,
            typeof(String), new Type[]{typeof(String)});
      // Generate IL for 'GetGreeting' method.
      ILGenerator myMethodIL = myHelloMethod.GetILGenerator();
      myMethodIL.Emit(OpCodes.Ldstr, "Hi! ");
      myMethodIL.Emit(OpCodes.Ldarg_1);
      MethodInfo infoMethod =
         typeof(String).GetMethod("Concat",new Type[]{typeof(string),typeof(string)});
      myMethodIL.Emit(OpCodes.Call, infoMethod);
      myMethodIL.Emit(OpCodes.Ret);

      MethodInfo myHelloMethodInfo =
         typeof(IMyInterface).GetMethod("HelloMethod");
      // Implement 'HelloMethod' of 'IMyInterface'.
      myNestedClassType.DefineMethodOverride(myHelloMethod, myHelloMethodInfo);
      // Create 'MyHelloWorld' type.
      Type myType = myHelloWorldType.CreateType();
      // Create 'MyNestedClass' type.
      return myNestedClassType.CreateType();
   }
}

.NET Framework
Available since 1.1
Silverlight
Available since 2.0
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