Mono.Cecil:从其他程序集调用GENERIC基类'方法

Question

我正在跟进我之前的问题:Mono.Cecil:从其他程序集中调用基类的方法.
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)

有什么改变？

Answer 1

在上一篇文章中,您表明您使用的代码如下:

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.您需要使用基类型中的适当通用信息重新创建相应的方法调用.

为简化起见,我们使用以下方法,取自Cecil测试套件:

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);