在类中实现一个C＃接口方法为什么必须是公开的？ [英] Why must an C# interface method implemented in a class be public?

问题描述

我有继承接口的类。接口成员方法在我的课没有实现访问修饰符（所以，默认情况下它是私有的）。

I have a class which inherits an interface. An interface member method is implemented in my class without an access modifier (so, by default it's private ) .

我得到的错误，因为它不是公共无法实现接口成员。

I am getting the error "cannot implement an interface member because it is not public".

为什么不允许？我能不能覆盖的无障碍？

Why it is not allowed? Can't I override the accessibility?

推荐答案

下面是一个例子的为什么的它没有意义的能够覆盖可见：

Here's an example of why it doesn't make sense to be able to override the visibility:

interface someI
{
    void doYourWork();
}
public class A : someI
{
    public void doYourWork()
    {
        //...
    }
}

public class B : someI
{
    private void doYourWork()
    {
        //...
    }
}
void Main()
{
    List<someI> workers = getWorkers();
    foreach(var worker in workers)
        worker.doYourWork();
}

当你的工人B型的，会发生什么？你调用一个方法，就好像它是公开的，但它是一个私有方法。如果你想要这个功能，那么它是不是一个真正的私有的方法是什么呢？

What happens when your worker is of type B? You're calling a method as if it were public, but it's a private method. If your want this functionality, then it's not really a private method is it?

如果您只能通过接口引用时，希望它是公开的，那么你可以将它定义为这样的：

If you only want it to be public when referenced through your interface, then you can define it as such:

public class B : someI
{
    void someI.doYourWork()
    {
        //...
    }
}

和你结束了这一点：

var b = new B();
b.doYourWork(); // Not accessible
((someI)b).doYourWork(); // Accessible

这篇关于在类中实现一个C＃接口方法为什么必须是公开的？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！