gistfile1.cs

private static void _GenerateMethod_With_Return(
    MethodInfo methodInfo, 
    TypeBuilder typeBuilder, 
    string firstMethodName, 
    Type[] parameterTypes)
{
    var returnType = methodInfo.ReturnType;
    var methodBuilder = typeBuilder.DefineMethod(
            firstMethodName,
            MethodAttributes.Public | MethodAttributes.Virtual,
            returnType,
            parameterTypes);
    methodBuilder.InitLocals = true;
    var methodIl = methodBuilder.GetILGenerator();

    methodIl.DeclareLocal(returnType);
    methodIl.Emit(OpCodes.Ldloc_0);
    methodIl.Emit(OpCodes.Ret);
}