zhangzhimin zhangzhimin - 9 months ago 54
C++ Question

How can I cast a base smart pointer into the derived one in C++?

Code :

class Base {

class Derived : public Base {
void OnlyOwnedByDerived{

The question is :
1. If I used a smart pointer of the Base class to reference the Derived one, the reason why I do so is that I want to get the benefit of dynamic binding which only fits virtual functions. But if I want to to use the function that is only owned by the derived class, what should I do ?
between the smart pointer of different class gives me an error...

  1. The most direct way I can come up with is use raw pointer rather than smart one...


In C++11, there is the dynamic_pointer_cast

Which you can use:

void func(std::shared_ptr<Base> b){
    if(auto d = dynamic_pointer_cast<Derived>(b)){
         ....more code