6

我正在跟进我之前的问题：Mono.Cecil: call base class' method from other assembly。
我正在做同样的事情，但如果我的基类是通用的，它就不起作用。 

//in Assembly A
class BaseVM<T> {}

//in Assembly B
class MyVM : Base<SomeModel> {
 [NotifyProperty]
 public string Something {get;set;}
}

它编织了以下代码：

L_000e: call instance void [AssemblyA]Base`1::RaisePropertyChanged(string)

代替 

L_000e: call instance void [AssemblyA]Base`1<class SomeModel>::RaisePropertyChanged(string)

有什么要改变的？

4

1 回答 1

21

在您之前的帖子中，您表示您正在使用如下代码：

TypeDefinition type = ...;
TypeDefintion baseType = type.BaseType.Resolve ();
MethodDefinition baseMethod = baseType.Methods.First (m => ...);
MethodReference baseMethodReference = type.Module.Import (baseMethod);
il.Emit (OpCodes.Call, baseMethodReference);

显然，这不适用于泛型：

当您Resolve ()使用 .BaseType 时，您将丢失通用实例化信息。您需要使用来自基类型的适当通用信息重新创建适当的方法调用。

为简化起见，让我们使用以下来自 Cecil 测试套件的方法：

public static TypeReference MakeGenericType (this TypeReference self, params TypeReference [] arguments)
{
    if (self.GenericParameters.Count != arguments.Length)
        throw new ArgumentException ();

    var instance = new GenericInstanceType (self);
    foreach (var argument in arguments)
        instance.GenericArguments.Add (argument);

    return instance;
}

public static MethodReference MakeGeneric (this MethodReference self, params TypeReference [] arguments)
{
    var reference = new MethodReference(self.Name,self.ReturnType) {
        DeclaringType = self.DeclaringType.MakeGenericType (arguments),
        HasThis = self.HasThis,
        ExplicitThis = self.ExplicitThis,
        CallingConvention = self.CallingConvention,
    };

    foreach (var parameter in self.Parameters)
        reference.Parameters.Add (new ParameterDefinition (parameter.ParameterType));

    foreach (var generic_parameter in self.GenericParameters)
        reference.GenericParameters.Add (new GenericParameter (generic_parameter.Name, reference));

    return reference;
}

有了这些，您可以将代码重写为：

TypeDefinition type = ...;
TypeDefintion baseTypeDefinition = type.BaseType.Resolve ();
MethodDefinition baseMethodDefinition = baseTypeDefinition.Methods.First (m => ...);
MethodReference baseMethodReference = type.Module.Import (baseMethodDefinition);
if (type.BaseType.IsGenericInstance) {
    var baseTypeInstance = (GenericInstanceType) type.BaseType;
    baseMethodReference = baseMethodReference.MakeGeneric (baseTypeInstance.GenericArguments.ToArray ());
}

il.Emit (OpCodes.Call, baseMethodReference);
于 2011-02-15T09:23:17.003 回答