释放抽象类指针
在C++中，我有一个类A，它有一个抽象类指针，以允许类B中包含多态性，我有另一个指向抽象类C<的指针/code> 将 B 类 的子类的具体实例分配到该内存中，我需要从 C 类 调用清理（参见下面的问题）函数来取消分配class 的子类占用的内存B 我从堆中分配的，问题是我不能保证我可以访问清理函数，因为我只有一个指向 class C 的指针，我不能复制它，因为当我调用需要销毁包含的类A时它可能已经消失了。
为了解决无法访问清理函数的问题，即使我指向子类，我是否可以在class A指针上调用delete？ C++ new 是否也像 malloc 一样存储堆块大小，以便您可以删除由指向这样的抽象类的指针引用的内存？如果没有，是否有另一种方法来组织允许我处理的程序情况如何？
In C++ I have a class A that has an abstract class pointer to allow for polymorphism contained in a class B, I have another pointer to an abstract class C that allocates a concrete instance of a child class of class B into that memory and I need to call a cleanup (see question below) function from class C to deallocate the memory taken by the child class of class B that I allocated from the heap, the problem is I can't guarantee I have access to the cleanup function because I only have a pointer to class C which I can't just copy, because it could be gone by the time I call need to destroy the containing class A.
In order to solve the problem of not having access to the cleanup function can I call delete on the class A pointer even though I'm pointing to a child class? Does C++ new also store heap block size like malloc so that you can just delete memory referenced by a pointer to an abstract class like this? If not is there another way to organize the program that allows me to handle the situation?
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我正在使用我的水晶球，因为很难理解你的问题，但你可能需要虚拟析构函数。
I'm using my crystal ball because it's hard to follow your question but you probably need virtual destructors.
该标准规定（§5.3.5 ¶3）：
如果我理解正确的话，您有一个某种派生类型的对象，并且持有一个指向它的指针，其静态类型是其基类之一；所以，只要你有虚拟析构函数，就可以了。
编辑好吧，我太慢了:P
The standard states (§5.3.5 ¶3):
If I understood correctly, you have an object of some derived type, and you hold a pointer to it whose static type is one of its base classes; so, you're ok, as far as you have
virtualdestructors.Edit well, I was way too slow :P