bad_typeid Exception


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The bad_typeid exception is thrown by the typeid operator when the operand for typeid is a NULL pointer.

      catch (bad_typeid)  

The interface for bad_typeid is:

class bad_typeid : public exception  
   bad_typeid(const char * _Message = "bad typeid");  
   bad_typeid(const bad_typeid &);  
   virtual ~bad_typeid();  

The following example shows the typeid operator throwing a bad_typeid exception.

// expre_bad_typeid.cpp  
// compile with: /EHsc /GR  
#include <typeinfo.h>  
#include <iostream>  
class A{  
   // object for class needs vtable  
   // for RTTI  
   virtual ~A();  
using namespace std;  
int main() {  
A* a = NULL;  
try {  
   cout << typeid(*a).name() << endl;  // Error condition  
catch (bad_typeid){  
   cout << "Object is NULL" << endl;  

Object is NULL  

Run-Time Type Information