什么是从嵌套类的封闭类访问领域的最佳途径？ [英] What's the best way of accessing field in the enclosing class from the nested class?

问题描述

说，如果我有一个形式的下拉菜单，我有这个类里面又嵌套类。
现在，什么是从嵌套类访问此下拉列表的最佳方式？

Say if I have a dropdown in a form and I have another nested class inside of this class . Now what's the best way to access this dropdown from the nested class?

推荐答案

与Java，嵌套类是不是一个特殊的内部类，所以你需要传递一个参考。雷蒙德陈有在这里描述的差别的例子： C＃嵌套类像C ++嵌套类，不的Java内部类。

Unlike Java, a nested class isn't a special "inner class" so you'd need to pass a reference. Raymond Chen has an example describing the differences here : C# nested classes are like C++ nested classes, not Java inner classes.

这里是嵌套类的构造函数传递，供日后参考外部类的实例的实例。

Here is an example where the constructor of the nested class is passed the instance of the outer class for later reference.

// C#
class OuterClass 
{
    string s;
    // ...
    class InnerClass 
    {
       OuterClass o_;
       public InnerClass(OuterClass o) { o_ = o; }
       public string GetOuterString() { return o_.s; }
    }
    void SomeFunction() {
        InnerClass i = new InnerClass(this);
        i.GetOuterString();
    }

}

请注意，将InnerClass可以访问取值的OuterClass，我没有修改雷蒙德code（我挂以上），所以记得该字符串s; 是私人，因为没有指定其他访问权限。

Note that the InnerClass can access the "s" of the OuterClass, I didn't modify Raymond's code (as I linked to above), so remember that the "string s;" is private because no other access permission was specified.

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