Question

我正在使用以下代码创建基于键/值的类类型：

    /// <summary>
    /// Generate a new class type using the schema info in a list of DataGridHeader
    /// </summary>
    /// <param name="header"></param>
    /// <returns></returns>
    static public Type BuildType(IList<DataGridHeader> header) {
        AppDomain domain = Thread.GetDomain();
        AssemblyName assemblyName = new AssemblyName {Name = "DynamicDataGridDataAsm"};
        AssemblyBuilder assemblyBuilder = domain.DefineDynamicAssembly(assemblyName,AssemblyBuilderAccess.RunAndSave);
        ModuleBuilder dynamicDataGridDataModule = assemblyBuilder.DefineDynamicModule("DynamicDataGridDataModule", "DynamicDataGridDataModule.dll");
        TypeBuilder ivTypeBld = dynamicDataGridDataModule.DefineType("DynamicDataGridData", TypeAttributes.Public);

        foreach (var kvp in header) {
            ImplementProperty(ivTypeBld, kvp.Name, typeof(string));
        }

        ImplementProperty(ivTypeBld, "Value", typeof(string));

        return ivTypeBld.CreateType();
    }

    /// <summary>
    /// Generates propery Get/Set methods for a property by name and type
    /// </summary>
    /// <param name="type"></param>
    /// <param name="propertyName"></param>
    /// <param name="propertyType"></param>
    private static void ImplementProperty(TypeBuilder type, string propertyName, Type propertyType) {
        FieldBuilder field = type.DefineField("_" + propertyName, propertyType, FieldAttributes.Private);

        PropertyBuilder property = type.DefineProperty(propertyName, PropertyAttributes.None, propertyType, Type.EmptyTypes);

        MethodBuilder getter = type.DefineMethod("get_" + propertyName, MethodAttributes.Public, propertyType, Type.EmptyTypes);
        ILGenerator getterIL = getter.GetILGenerator();
        getterIL.Emit(OpCodes.Ldarg_0);
        getterIL.Emit(OpCodes.Ldfld, field);
        getterIL.Emit(OpCodes.Ret);

        MethodBuilder setter = type.DefineMethod("set_" + propertyName, MethodAttributes.Public, typeof(void), new Type[] { propertyType });
        ILGenerator setterIL = setter.GetILGenerator();
        setterIL.Emit(OpCodes.Ldarg_0);
        setterIL.Emit(OpCodes.Ldarg_0);
        setterIL.Emit(OpCodes.Ldflda, field);
        setterIL.Emit(OpCodes.Ldarg_1);
        setterIL.Emit(OpCodes.Ldstr, propertyName);
        setterIL.Emit(OpCodes.Call, propertyType);
        setterIL.Emit(OpCodes.Ret);

        property.SetGetMethod(getter);
        property.SetSetMethod(setter);
    }

构建类型后，我尝试使用字典值填充新属性成员：

        static public object GetInstance(Type type, Dictionary<string, string> data) {
            //default construct the new type
            ConstructorInfo constructorInfo = type.GetConstructor(Type.EmptyTypes);
            object row = constructorInfo.Invoke(null);

            //Call set on each property
            foreach (var kv in data) {
                try {
//                    PropertyInfo prop = row.GetType().GetProperty(kv.Key, BindingFlags.Public | BindingFlags.Instance);
//                    if (null != prop && prop.CanWrite) {
//                        prop.SetValue(row, kv.Value, null);
//                    }

                    type.InvokeMember(kv.Key,
                        BindingFlags.Instance | BindingFlags.Public | BindingFlags.SetProperty,
                        Type.DefaultBinder,
                        row,
                        new object[] {kv.Value});
                }
                catch (Exception e) {
                    Console.WriteLine(e);
                }
            }

调用InvokeMember或PropertyInfo.SetValue导致异常

“{System.Reflection.TargetInvocationException：调用目标抛出了异常.---＆gt; System.BadImageFormatException：错误的方法标记。 at DynamicDataGridData.set_Value（String） ---内部异常堆栈跟踪结束--- at System.RuntimeMethodHandle.InvokeMethod（Object target，Object [] arguments，Signature sig，Boolean constructor） at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal（Object obj，Object [] parameters，Object [] arguments）在System.Reflection.RuntimeMethodInfo.Invoke（Object obj，BindingFlags invokeAttr，Binder binder，Object []参数，CultureInfo文化） at System.RuntimeType.InvokeMember（String name，BindingFlags bindingFlags，Binder binder，Object target，Object [] providedArgs，ParameterModifier [] modifiers，CultureInfo culture，String [] namedParams） at System.Type.InvokeMember（String name，BindingFlags invokeAttr，Binder binder，Object target，Object [] args） at DSI.MobileClient.Models.DataGridDataTypeBuilder.GetInstance（Type type，Dictionary`2 data）in c：\ DSISource_Global \ v7 \ Development \ Team5 \ DSI.MobileClient \ Models \ DataGridDataTypeBuilder.cs：line 33}“

我一直在调查set属性构建器的.Emit部分中可能出现的问题，但是我还没想到我错过了什么。

调试器显示我正在尝试设置的属性。

**修改

认为这条线不正确：

setterIL.Emit(OpCodes.Call, propertyType);

现在尝试理解复制和粘贴 - 用此替换setter emit可能有效：

    setterIL.Emit(OpCodes.Ldarg_0);
    setterIL.Emit(OpCodes.Ldarg_1);
    setterIL.Emit(OpCodes.Stfld, field);
    setterIL.Emit(OpCodes.Ret);

动态类型 - 属性setter上的InvokeMember抛出异常

0 个答案: