std::bad_cast

 

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std::bad_cast

Member functions

bad_cast::bad_cast

Inherited from std::exception

exception::~exception

exception::what

 

Defined in header <typeinfo>
class bad_cast : public std::exception;

An exception of this type is thrown when a dynamic_cast to a reference type fails the run-time check (e.g. because the types are not related by inheritance).

Inheritance diagram

Member functions

(constructor)	constructs a new bad_cast object (public member function)

Inherited from std::exception

Member functions

(destructor) [virtual]	destructs the exception object (virtual public member function of std::exception)
what [virtual]	returns an explanatory string (virtual public member function of std::exception)

Example

run this code

#include <iostream>
#include <typeinfo>
 
struct Foo { virtual void f() {} };
struct Bar { virtual void f() {} };
 
int main()
{
    Bar b;
    try {
        Foo& f = dynamic_cast<Foo&>(b);
    } catch(const std::bad_cast& e)
    {
        std::cout << e.what() << '\n';
    }
}

Output:

Bad dynamic_cast!