相关疑难解决方法(0)

给定以下结构:

public struct Foo<T>
{
   public Foo(T obj) { }

   public static implicit operator Foo<T>(T input)
   {
      return new Foo<T>(input);
   }
}

此代码编译:

private Foo<ICloneable> MakeFoo()
{
    string c = "hello";
    return c; // Success: string is ICloneable, ICloneable implicitly converted to Foo<ICloneable>
}

但是这段代码没有编译 - 为什么？

private Foo<ICloneable> MakeFoo()
{
    ICloneable c = "hello";
    return c; // Error: ICloneable can't be converted to Foo<ICloneable>. WTH?
}

说,我有一个界面

public interface ISomeControl
{
    Control MyControl { get; }
    ...
}

是否可以像这样定义smth:

public static implicit operator Control(ISomeControl ctrl)
{
    return ctrl.MyControl;
}

或者更确切地说,为什么我不能在C#中这样做？