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遵守以下簡單的源代碼:如何使用reflection.emit發出顯式接口實現?
using System;
using System.Linq.Expressions;
using System.Reflection;
using System.Reflection.Emit;
namespace A
{
public static class Program
{
private const MethodAttributes ExplicitImplementation =
MethodAttributes.Private | MethodAttributes.Virtual | MethodAttributes.Final |
MethodAttributes.HideBySig | MethodAttributes.NewSlot;
private const MethodAttributes ImplicitImplementation =
MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.HideBySig;
private static Type EmitMyIntfType(ModuleBuilder moduleBuilder)
{
var typeBuilder = moduleBuilder.DefineType("IMyInterface",
TypeAttributes.NotPublic | TypeAttributes.Interface | TypeAttributes.Abstract);
typeBuilder.DefineMethod("MyMethod", MethodAttributes.Assembly | MethodAttributes.Abstract |
MethodAttributes.Virtual | MethodAttributes.HideBySig | MethodAttributes.NewSlot,
typeof(void), new[] { typeof(int) });
return typeBuilder.CreateType();
}
public static void Main()
{
var assemblyName = new AssemblyName("DynamicTypesAssembly");
var assemblyBuilder = AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName, AssemblyBuilderAccess.RunAndSave);
var moduleBuilder = assemblyBuilder.DefineDynamicModule(assemblyName.Name, assemblyName.Name + ".dll", true);
var myIntfType = EmitMyIntfType(moduleBuilder);
var typeBuilder = moduleBuilder.DefineType("MyType",
TypeAttributes.Public | TypeAttributes.BeforeFieldInit | TypeAttributes.Serializable |
TypeAttributes.Sealed, typeof(object), new[] { myIntfType });
//var myMethodImpl = typeBuilder.DefineMethod("IMyInterface.MyMethod", ExplicitImplementation,
// null, new[] { typeof(int) });
var myMethodImpl = typeBuilder.DefineMethod("MyMethod", ImplicitImplementation,
null, new[] { typeof(int) });
var ilGenerator = myMethodImpl.GetILGenerator();
ilGenerator.Emit(OpCodes.Ret);
var type = typeBuilder.CreateType();
assemblyBuilder.Save("A.dll");
}
}
}
以下是使用反射器由反編譯獲得的A.DLL裝配等效C#代碼:
internal interface IMyInterface
{
void MyMethod(int);
}
[Serializable]
public sealed class MyType : IMyInterface
{
public override void MyMethod(int)
{
}
}
現在,如果我希望MyType
類型實施明確界面IMyInterface
? 所以我把這些線:
//var myMethodImpl = typeBuilder.DefineMethod("IMyInterface.MyMethod", ExplicitImplementation,
// null, new[] { typeof(int) });
var myMethodImpl = typeBuilder.DefineMethod("MyMethod", ImplicitImplementation,
null, new[] { typeof(int) });
和切換的意見,得到這個代碼:
var myMethodImpl = typeBuilder.DefineMethod("IMyInterface.MyMethod", ExplicitImplementation,
null, new[] { typeof(int) });
// var myMethodImpl = typeBuilder.DefineMethod("MyMethod", ImplicitImplementation,
// null, new[] { typeof(int) });
但現在,應用程序無法創建動態類型。這條線:
var type = typeBuilder.CreateType();
拋出以下異常:
System.TypeLoadException was unhandled
Message="Method 'MyMethod' in type 'MyType' from assembly 'DynamicTypesAssembly, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' does not have an implementation."
Source="mscorlib"
TypeName="MyType"
StackTrace:
at System.Reflection.Emit.TypeBuilder._TermCreateClass(Int32 handle, Module module)
at System.Reflection.Emit.TypeBuilder.TermCreateClass(Int32 handle, Module module)
at System.Reflection.Emit.TypeBuilder.CreateTypeNoLock()
at System.Reflection.Emit.TypeBuilder.CreateType()
at A.Program.Main() in C:\Home\work\A\Program.cs:line 45
InnerException:
誰能告訴我什麼是錯我的代碼?
謝謝。
確實是這樣,但我也注意到了這個問題,甚至訪問MSDN文章,但閱讀備註部分的第一段後放棄了它。只是沒有將顯式接口實現視爲給接口方法另外命名。現在我看到了我的錯誤。謝謝。 – mark
這就是爲什麼代碼審查的作品! ) –