Typeid issues to determine what data is processed

Question

Why does this return false and how can I fix it? I'm trying to make a program that writes data to a file and can read that file back in and display it. Also, there are 3 classes. One is a parent class (MyEmployee not displayed) and the Hourly and Salaried classes are child classes.

  for (int i = 0; i < ARRAY_SIZE; i++)
        {
            MyEmployee* empPtr = payroll[i];
            if (typeid(*empPtr) == typeid(Hourly))
            {
                Hourly* empHPtr = static_cast<Hourly*>(empPtr);
            }
            else if (typeid(*empPtr) == typeid(Salaried))
            {
                Salaried* empSPtr = static_cast<Salaried*>(empPtr);
            }
        }
        for (int i = 0; i < ARRAY_SIZE; i++)
        {
            payroll[i]->writeData(myWrittenFile);
        }

Answer 1

If MyEmployee is polymorphic use dynamic_cast < type-id > ( expression ) This Converts the operand expression to an object of type type-id and will return 0 if the conversion fails.

MyEmployee* empPtr = payroll[i];
if (dynamic_cast<Hourly*>(empPtr))
{
  ...
} 

Answer 2

I'm going to guess that your class hierarchy is:

struct MyEmployee { virtual ~MyEmployee() {}; /* ... */ };

struct Hourly : MyEmployee { /* ... */ };
struct Salaried : MyEmployee { /* ... */ };

If so, then you could replace your code with:

MyEmployee *empPtr = payroll[i];
Hourly *empH = dynamic_cast<Hourly *>(empPtr);
Salaried *empS = dynamic_cast<Salaried *>(empPtr);

The empH and empS will be null if the object was not of that type; and a valid pointer if it was of that type.

Of course, it may be better to replace this whole thing with a virtual function, as chris suggested.