typeinfo::bad_cast in C++ with Examples

Standard C++ contains several built-in exception classes. typeinfo::bad_cast is one of them. This is an exception thrown on failure to dynamic cast. Below is the syntax for the same: Header File:

<typeinfo>

Syntax:

class bad_cast;

Note: To make use of std::bad_cast, one should set up the appropriate try and catch blocks. Return Value: It doesn't return anything. Below are the examples to understand the implementation of std::bad_cast in a better way: Program 1:

CPP14

// C++ code for std::bad_cast
#include <bits/stdc++.h>
#include <typeinfo>

using namespace std;

// Base Class
class Base {
    virtual void member() {}
};

// Derived Class
class Derived : Base {
};

// main() method
int main()
{

    // try block
    try {
        Base gfg;
        Derived& rd
            = dynamic_cast<Derived&>(gfg);
    }

    // catch block to handle the errors
    catch (bad_cast& bc) {
        cerr << "bad_cast caught: "
             << bc.what() << endl;
    }

    return 0;
}

Output:

bad_cast caught: std::bad_cast

Program 2:

CPP14

// C++ code for std::bad_cast
#include <bits/stdc++.h>
#include <typeinfo>

using namespace std;

// Base Class
class Base {
    virtual void member() {}
};

// Derived Class
class Derived : Base {
};

// main() method
int main()
{

    // try block
    try {
        Base geeksforgeeks;
        Derived& abc
            = dynamic_cast<Derived&>(
                geeksforgeeks);
    }

    // catch block to handle the errors
    catch (bad_cast& a) {
        cerr << "bad_cast caught: "
             << a.what() << endl;
    }

    return 0;
}

Output:

bad_cast caught: std::bad_cast

Reference: https://cplusplus.com/reference/typeinfo/bad_cast/

typeinfo::bad_cast in C++ with Examples

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