#include <memory>
#include <iostream>
#include <type_traits>
class base{
public:
base(){std::cout << "base" << std::endl;}
~base(){std::cout << "~base" << std::endl;}
void print(){std::cout << "base::print" << std::endl;}
};
class derived:public base{
public:
derived(){std::cout << "derived" << std::endl;}
~derived(){std::cout << "~derived" << std::endl;}
void print(){std::cout << "derived::print" << std::endl;}
};
template<typename T>
std::shared_ptr<
typename std::enable_if<(!std::is_same<base,T>::value)
&&(std::is_base_of<base,T>::value),T>::type
>
dyn_cast(std::shared_ptr<base> ptr){
return std::static_pointer_cast<T>(ptr);
}
int main()
{
std::shared_ptr<base> b_ptr = std::make_shared<derived>();
b_ptr->print();
auto d_ptr = dyn_cast<derived>(b_ptr);
d_ptr->print();
return 0;
}
[c++]shared_ptr类型转换
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转载自blog.csdn.net/adream307/article/details/81607946
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