可以比较 RUNTIME_CLASS() 宏返回的指针吗？
我有一个函数，它需要 CRuntimeClass 指针列表来设置视图。如果使用已设置的相同类的列表调用该函数，我想返回而不执行任何操作。保存指针值并在下一次调用时比较它们当前正在工作，但我想验证这是合法的事情，而不是偶然发生的事情。也许我的 doc-search-fu 缺少，但我找不到任何地方可以保证从给定类的 RUNTIME_CLASS() 宏返回的指针值在程序的生命周期中是相同的。我能找到的最接近的是 CObject::GetRuntimeClass( ）：
每个 CObject 派生类都有一个 CRuntimeClass 结构。
这意味着指针值不应更改，但并未明确说明。有人对此有更具体的了解吗？或者有更好的方法来比较 CRuntimeClasses 吗？
I've got a function that takes a list of CRuntimeClass pointers in order to setup a view. I'd like to return without doing anything if the function is called with a list of the same classes that are already setup. Saving the pointer values and comparing them on the next call is currently working, but I want to verify that that's a legal thing to do, and not something that just happens to work. Maybe my doc-search-fu is lacking, but I can't find anywhere that guarantees the pointer value returned from the RUNTIME_CLASS() macro for a given class will be the same for the life of the program. The closest I could find is in the docs for CObject::GetRuntimeClass():
There is one CRuntimeClass structure for each CObject-derived class.
That implies that the pointer value shouldn't change, but doesn't exactly state it. Does anyone have something a bit more concrete on that? Or is there a better way to compare the CRuntimeClasses?
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尽管有可能，但没有记录这样的保证。您应该使用 CObject::IsKindOf()。
No such guarantee is documented, albeit that it is likely. You are supposed to use CObject::IsKindOf().
查看
afx.h并进行一些调试表明RUNTIME_CLASS()返回一个指向静态成员的指针：static CRuntimeClass class##class_name （可以在DECLARE_DYNAMIC(class_name)宏的定义中看到）。由于该成员是静态的，因此指向它的指针在运行时不会改变。换句话说，
static是您的保证。Taking a peek at
afx.hplus a little of debugging shows thatRUNTIME_CLASS()returns a pointer to a static member:static CRuntimeClass class##class_name(as it can be seen in the definition ofDECLARE_DYNAMIC(class_name)macro).As the member is static, the pointer to it does not change during runtime. In other words
staticis your guarantee.