blocks|key|1270202|text|不，B类没有指向A类的指针，除非您显式添加它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1270203|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

No, Class B does not have a pointer to Class A, unless you explicitly add it.

blocks|key|1270279|text|否--在C%2B%2B中，嵌套类只影响名称和可见性，而不影响类本身的语义。就生成的代码而言，嵌套的类与未嵌套的类没有什么不同。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1270280|所有更改的是可见性和名称(例如，如果它位于外部类的private:部分，则对外部世界不可见，如果位于public:部分，则它是可见的，但(当然)要将其命名为outer_class::inner_class。但它仍然是一个完全独立的类--例如，您可以创建内部类的实例，而不创建外部类的任何实例。|offset|length|style|CODE|1270281|编辑:对不起，我错过了你问题的一部分。在C%2B%2B+0x中，内部类确实可以访问外部类的私有部分--本质上，就好像外部类已经将内部类声明为它的朋友，所以私有名称是可见的，但是在调用外部类的任何非静态成员函数之前，您仍然需要将它传递给外部类的对象的引用。|1270282|虽然现在还不是这样，但我相信大多数编译器已经实现了这一部分。|1270283|entityMap^0|0|P|8|1E|7|26|O|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@$D|P|E|Q|F|G]|$D|R|E|S|F|G]|$D|T|E|U|F|G]]|9|@]|A|$]]|$1|H|3|I|5|6|7|V|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|W|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|X|8|@]|9|@]|A|$]]]|M|$]]

No -- in C++, nesting classes only affects names and visibility, not the semantics of the class itself. As far as generated code goes, the nested class is no different from one that isn't nested.

All that's changed is the visibility and the name (e.g. if it's in a <code>private:</code> section of the outer class, it's not visible to the outside world, and if it's in a <code>public:</code> section, it's visible, but (of course) to name it you use <code>outer_class::inner_class</code>. It's still a completely separate class though -- just for example, you can create an instance of the inner class without creating any instance of the outer class.

Edit: Sorry, I missed part of your question. In C++ 0x, the inner class does have access to the the private parts of the outer class -- in essence, it's as if the outer class has declared the inner class as its friend, so private names are visible, but you still need to pass it something like a reference to an object of the outer class before it can invoke any non-static member functions of the outer class.

Although this isn't supposed to be the case yet, I believe most compilers implement this particular part already.

blocks|key|1055571|text|它是否有指向父对象的指针:没有。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1055572|它是否有权访问父母的私有成员:某种程度上|1055573|我认为，如果标准中没有很好地定义它是否具有访问权限，我可能就错了。|1055574|但您可以在g%2B%2B中访问它|1055575|#include+<iostream>

class+X
{
++++class+Y
++++{
++++++++public:
++++++++++++Y(X*+p)
++++++++++++++++:parent(p)
++++++++++++{}
++++++++++++void+TryY()
++++++++++++{
++++++++++++++++//+Access+a+private+member+of+X
++++++++++++++++%2B%2B(parent->value);
++++++++++++}

++++++++private:
++++++++++++X*++parent;
++++};

++++public:
++++++++X()
++++++++++++:y(this)
++++++++{
++++++++++++value+=+4;
++++++++}

++++++++void+TryY()
++++++++{
++++++++++++y.TryY();
++++++++++++std::cout+<<+value+<<+std::endl;
++++++++}
++++private:
++++++++Y+++y;
++++++++int+value;

};

int+main()
{
++++X+++x;
++++x.TryY();
}|code-block|syntax|javascript|1055576|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|Q|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|R|8|@]|9|@]|A|$]]|$1|H|3|I|5|J|7|S|8|@]|9|@]|A|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Does it have a pointer to the parent: No. 
Does it have access to the parents private members: Sort of 

I think the if it has access is not well defined in the standard I could be wrong. 
But you can access it in g++

<pre><code>#include &lt;iostream&gt;

class X
{
 class Y
 {
 public:
 Y(X* p)
 :parent(p)
 {}
 void TryY()
 {
 // Access a private member of X
 ++(parent-&gt;value);
 }

 private:
 X* parent;
 };

 public:
 X()
 :y(this)
 {
 value = 4;
 }

 void TryY()
 {
 y.TryY();
 std::cout &lt;&lt; value &lt;&lt; std::endl;
 }
 private:
 Y y;
 int value;

};

int main()
{
 X x;
 x.TryY();
}
</code></pre>

HI,

In C++ inner class,

<pre><code>class A {
 public: 
 void f1();
 private:
 void f2();
 class B {
 private void f3(); 
 };

 }
</code></pre>

Does an inner class (B) has a pointer to its parent class (A)? (like it does in Java).
And can B calls its parent class public/private method (like it does in Java).

Thank you.

Question about C++ inner class

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Java

嗨,在C++内部类中，class A {    public:          void f1();    private:         void f2();    class B {       private void f3();     }; }内部类(B)是否有指向其父类(A)的指针？(就像在Java中一...

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