C++從派生類指針獲取基類對象？

Question

假設我有Derived * derivedPtr;
我想從derivedPtr的Base baseObject;

Base baseObject = * derivedPtr;會用適當的Base類成員變量創建baseObject？

謝謝

Answer 1

這是Object Slicing

Derived* obj = new Derived; 
base objOne = (*obj) ; // Object slicing. Coping only the Base class sub-object 
         // that was constructed by eariler statement. 

Answer 2

是的。這實際上稱爲「切片」，因爲您只需從派生類中刪除所有內容即可。

Answer 3

您可以使用動態鑄造做到這一點。

例如

Base* baseObject = dynamic_cast<Base*>(derivedPtr); 

http://www.cplusplus.com/doc/tutorial/typecasting/