C#,对象和多个接口实现:如何正确使用？

Question

所以我有两个接口:

public interface ISomething
{
    public int A();
}


public interface ISomethingElse
{
    public int B();
}

并且实现两者的对象:

public class MyObject : ISomething, ISomethingElse
{      
}

现在我有这个运行代码:

...
List<MyObject> objects = myObjectManager.SelectAll(); // now have say 10 MyObject

MyUtilityClass myUtilityClass = new MyUtilityClass();
MyOtherUtilityClass myOtherUtilityClass = new MyOtherUtilityClass();
myUtilityClass.MySpecialMethod(objects);                  // <- compile failure
myOtherUtilityClass.MySpecialMethod(objects);             // <- another failure
...

如果我想在所有这些上调用A或B,我该如何编写如下代码:

public class MyUtilityClass
{
    public void MySpecialMethod(List<ISomething> objects) // <- the problem
    {
        foreach (ISomething o in objects)
            o.A();   
    }
}

public class MyOtherUtilityClass
{
    public void MySpecialMethod(List<ISomethingElse> objects) // <- the problem
    {
        foreach (ISomethingElse o in objects)
            o.B();   
    }
}

我怎样才能干净地打电话MyUtilityClass.MySpecialMethod()给我List<MyObject> objects？没有所有类型转换是否可能？参数MyUtilityClass.MySpecialMethod()似乎是问题(我想将参数定义为实现ISomething的对象列表).

Answer 1

您可以使用IEnumerable<>界面而不是List<>.IEnumerable<>是协变的.