Thread: Type checking

I have two classes that are derived from a base class.

Is there a way to check what type of class it is at runtime?

Only thing I can come up with is having a virtual function that return a int and then have a global enum. But I assume that thats a bad solution.

Thanks.

I have a need to add the total of one of the variables for each of the derived classes I have.

I think this has something to do with dynamic_cast?

Code:

class Base
{
    privat:
       int trackTime;
}

class raceCar : public Base
{}

class crapCar : public Base
{}

int main()
{
    Base *carList[10];

    // Create some raceCars and crapCars
    .....

    int raceCarTotalTime = 0;
    int crapCarTotalTime = 0;

    for(carList)
    {
        if(carList[i] == raceCar)
             raceCarTotalTime += carList[i]->getTime();
        else
            crapCarTotalTime += carList[i]->getTime();
    }
}

I was thinking of that.

Something like:

if(carList[i].getType() == "RaceCar)
//Do this

But though that there maybe was a better way of doing it?

Well no, if you need to get the time from each class, make getTime virtual. Then it will make sure you return the correct time for each class.

But how can I then add it to two different variables depending on which class it belongs to?

Yes, I know how to create virtual functions. But when using virtual functions like you posted, I have no way of knowing of the time variable comes from a raceCar object or a crapCar object

Say I have a racing game where there are two teams. Team one are all using raceCar objects, team two are crapCars.

The two classes have all the normal move(), draw() and so one. They also have a variable to see how long the car has been on the track.

At the end of the game, I want to add up the total time all the raceCars have been on the track, and the total time all the crapCars have been on the track to see who was on the track the most. In order to add in into two different variables, I need to know which class the variable comes from.

Originally Posted by h3ro

Say I have a racing game where there are two teams. Team one are all using raceCar objects, team two are crapCars.

The two classes have all the normal move(), draw() and so one. They also have a variable to see how long the car has been on the track.

At the end of the game, I want to add up the total time all the raceCars have been on the track, and the total time all the crapCars have been on the track to see who was on the track the most. In order to add in into two different variables, I need to know which class the variable comes from.

What if each team has both raceCars and crapCars? Or raceCars, crapCars, and the newly created superCars and bonzoCars? Your code will become a hive of switch statements and type interrogation. Blech.

Just make each team manage a collection of base car pointers and use virtual functions to total the time, move, draw, etc.

Just make each team manage a collection of base car pointers and use virtual functions to total the time, move, draw, etc.

I cant. They have to be in the same array.

What if each team has both raceCars and crapCars? Or raceCars, crapCars, and the newly created superCars and bonzoCars? Your code will become a hive of switch statements and type interrogation. Blech.

There will never be a mix between then and never more then two car types. The project is done, adding up scores at the end is the only part that is left