c# - 类嵌套和访问修饰符

Question

我有以下代码:

class A
{
    public C GetC()
    {
        return new C();
    }
}

class B
{
    //has access to A but can not create C. Must ask A to create C.
    private void method()
    {
        A a = new A();
        C c = a.GetC();//Ok!
        C c2 = new C();//Not allowed.
    }
}

class C
{

}

应该在 C 上使用什么访问修饰符，以便只能通过 A 访问它？ (只有A类知道如何正确初始化C类) 或者有更好的解决方案吗？

Answer 1

如果将 A 设为 C 中的嵌套类，它应该可以工作。

public class B
{
    //has access to A but can not create C. Must ask A to create C.
    private void method()
    {
        var a = new C.A();
        var c = a.GetC();//Ok!
        var c2 = new C();//Not allowed.
    }
}

public class C
{
    private C()
    {
    }

    public class A
    {
        public C GetC()
        {
            return new C();
        }
    }
}