dynamic_pointer_cast Function
Dynamic cast to shared_ptr.
template <class Ty, class Other>
shared_ptr<Ty> dynamic_pointer_cast(const shared_ptr<Other>& sp);
Parameters
Ty
The type controlled by the returned shared pointer.Other
The type controlled by the argument shared pointer.sp
The argument shared pointer.
Remarks
The template function returns an empty shared_ptr object if dynamic_cast<Ty*>(sp.get()) returns a null pointer; otherwise it returns a shared_ptr Class<Ty> object that owns the resource that is owned by sp. The expression dynamic_cast<Ty*>(sp.get()) must be valid.
Example
// std_tr1__memory__dynamic_pointer_cast.cpp
// compile with: /EHsc
#include <memory>
#include <iostream>
struct base
{
virtual ~base()
{
}
int val;
};
struct derived
: public base
{
};
int main()
{
std::shared_ptr<base> sp0(new derived);
std::shared_ptr<derived> sp1 =
std::dynamic_pointer_cast<derived>(sp0);
sp0->val = 3;
std::cout << "sp1->val == " << sp1->val << std::endl;
return (0);
}
sp1->val == 3
Requirements
Header: <memory>
Namespace: std