how to check if the object is base class type

Question

I have the following inheritance hierarchy

class A{
  virtual bool fun() = 0;
};

class B: public A{
...
}

class C: public B{
...
}

class D: public C{
...
}

class E: public B{
...
}

in the main program I am executing like

for(auto pA: ObjVector)
{
   if(pA->fun()){
       ...
   }
}

Now I would like to know pA is contains the base class B object. As far as I know 2 ways

1. dynamic_cast the object and test for all derived classes if it fails for all dynamic_casts and only pass for B we are sure that the object is of type B

2. Add one more interface method that will return the type enumeration value and identify the B object.

Is there is any other method to identifying the B class?

Answer 1

You can use the typeid operator. For example

if (typeid(*pA) == typeid(B)) {
    /* ... ptr points to a B ... */
}

this work ONLY when pA is exactly B

typeid - documentation