与同一接口列表的接口

I have the following interface:

我有以下界面：

public interface IObject{
double x {get;}
double y {get;}
List<IObject> List{get; set;}
}

and this class

和这堂课

public class Holder<T> where T : IObject {
private T myItem;
public void ChangeItemList(T item){
myItem.List = item.List;
}

However the compiler doesn't like the ChangeItemList method and on this line :

但是编译器不喜欢ChangeItemList方法并且在这一行：

myItem.List = item.List;

gives me this error:

给我这个错误：

Cannot convert source type 'List<T>' to target type 'List<IObject>'

Why can't I do it and what is a good solution for this scenario? thank you

为什么我不能这样做，这个场景有什么好的解决方案？谢谢

2 个解决方案

#1

I am not sure what you want to achieve but the following compiles and runs without exceptions:

我不确定你想要实现什么，但以下编译和运行没有例外：

class Program
{
    static void Main(string[] args)
    {
        var holder = new Holder<IObject>();
        holder.MyItem = new Object { List = new List<IObject>() };
        holder.ChangeItemList(new Object { List = new List<IObject>() });
    }
}

public class Object : IObject
{
    public List<IObject> List { get; set; }
}

public interface IObject
{
    List<IObject> List { get; set; }
}

public class Holder<T> where T : IObject
{
    public T MyItem { get; set; }

    public void ChangeItemList(T item)
    {
        MyItem.List = item.List;
    }
}

#2

Try to do this one- worked for me. The problem i had that myItem was null.

尝试这样做 - 为我工作。我的问题是myItem为null。

public class Holder<T> where T : IObject
{
    private T myItem = Activator.CreateInstance<T>();

    public void ChangeItemList(T item)
    {
        myItem.List = item.List;
    }
}

#1