如何在运行时反映接口类型<t>

Question

我有多个数据点和每个相关的数据处理器。public interface IDataPointProcessor<T> where T : DataPointInputBase{    DataPointOutputBase GetOutput(T input);}我从文件加载数据点列表，并希望使用其单个关联处理器处理它们。foreach (DataPointInputBase item in input.DataPoints){    //assuming item coming in is of type 'X' how do I get correct processor    var type = typeof(IDataPointProcessor<X>);    var types = AppDomain.CurrentDomain.GetAssemblies()                .SelectMany(s => s.GetTypes())                .Where(p => type.IsAssignableFrom(p) && !p.IsAbstract);    IDataPointProcessor<X> matchedType = ??}我如何解决“X”以便我可以实例化它并处理输入？更新 #1 结合下面来自 Slava 和 Lucky 的答案，我得到以下结果，但它引发了一个异常——“对象与目标类型不匹配。” 即使在调试器中看起来一切都很好。是否可以转换为 IDataPointProcessor<> 并干净地调用接口方法，即： instance.GetOutput(item);foreach (DataPointInputBase item in input.DataPoints){    Type typeGenArg = item.GetType();    Type typeInterfaceGen = typeof(IDataPointProcessor<>).MakeGenericType(typeGenArg);    Type type = AppDomain.CurrentDomain.GetAssemblies()        .SelectMany(x => x.GetTypes())        .Where(x => typeInterfaceGen.IsAssignableFrom(x) && !x.IsAbstract)        .FirstOrDefault();    Type genericType = typeof(IDataPointProcessor<>);    Type dependedGenericType = genericType.MakeGenericType(typeof(DataPointInputBase));    var method = dependedGenericType.GetMethod("GetOutput");    var instance = Activator.CreateInstance(type);    //currently throws:System.Reflection.TargetException: 'Object does not match target type.'    var result = method.Invoke(instance, new object[] { item });    //Ideally I want to do this and avoid the magic strings etc    //var temp_output = instance.GetOutput(item);}

Answer 1

首先，你应该像这样使你的界面协变。

public interface IDataPointProcessor<in T> where T : DataPointInputBase

{

    DataPointOutputBase GetOutput(T input);

}

您应该检索由 实现的类型IDataPointProcessor<>，然后您应该创建检索类型的实例并调用泛型类型的方法。

Type genericType = typeof(IDataPointProcessor<>);

var types = AppDomain.CurrentDomain.GetAssemblies()

    .SelectMany(s => s.GetTypes())

    .Where(p => genericType.IsAssignableFrom(p) && !p.IsAbstract).ToList();

var dependedGenericType = genericType.MakeGenericType(typeof(DataPointInputBase));

var method = dependedGenericType.GetMethod("GetOutput");

var instance = Activator.CreateInstance(types[0]);

method.Invoke(instance, new object[] { new DataPointInputBase() });