C# - How To Check Object Type Using If Statement

Question

i'm currently writing an application with a parent class named 'Vehicle' and two children classes named 'Car' and 'Truck'. My problem is that I would like to search through the full list of Vehicles and return only each car, or each truck depending on what object is placed into a method. Right now I have had to write a method for ach search term such as below:

public string searchCarsByName(string nameString)
    {
        string carNames = "";
        foreach (Car car in Vehicles.OfType<Car>())
        {
            if (car.Name.Contains(nameString))
            {
                carNames += car.ToString();
            }
        }

        if (carNames == "")
        {
            return "No cars found";
        }
        else
        {
            return carNames;
        }
    }

   public string searchTrucksByName(string nameString)
    {
        string truckNames = "";
        foreach (Truck truck in Vehicles.OfType<Truck>())
        {
            if (truck.Name.Contains(nameString))
            {
                truckNames += name.ToString();
            }
        }

        if (truckNames == "")
        {
            return "No vehicle found";
        }
        else
        {
            return truckNames;
        }
    }

My only problem is that the names isn't the only way I would like to search, so for each search I am going to perform then I will have to write two methods. What i'm looking for is a way to pass in an Object to the method, and then dependent on the object it will append the necessary details to the string such as below:

    public string searchVehiclesByName(Vehicle nameString)
    {
        string vehicleNames = "";
    if(Vehicle.Type == car)
    {
        foreach (Car car in Vehicles.OfType<Car>())
        {
            if (car.Name.Contains(nameString))
            {
                vehicleNames += car.ToString();
            }
        }
    }
    else
   {

        foreach (Truck truck in Vehicles.OfType<Truck>())
        {
            if (truck.Name.Contains(nameString))
            {
                vehicleNames += truck.ToString();
            }
        }            
    }
    if (vehicleNames == "")
        {
            return "No vehicles found";
        }
        else
        {
            return vehicleNames;
        }
    }

}

Essentially what I need is a way to pass in a parent object and check if an object is of a certain child type before creating the resultant string, rather than having to pass each individual type of child object into a method to get the results I want.

Thank you in advance.

check this answer. http://stackoverflow.com/questions/983030/type-checking-typeof-gettype-or-is — Mana, May 10 '16 at 12:47
Do *all* vehicles have a *name*? Perhaps the `Name` property should be on the vehicle class? — musefan, May 10 '16 at 13:26

score 0 · Answer 1 · edited May 23 '17 at 12:07

Please have a look at this: Type Checking: typeof, GetType, or is?

public string searchVehiclesByName(Vehicle vehicle)
{
    string vehicleNames = "";
    if(vehicle.GetType() == typeof(Car))
    {
        foreach (Car car in Vehicles.OfType<Car>())
        {
            if (car.Name.Contains(nameString))
            {
                vehicleNames += car.ToString();
            }
        }
    }
    else
    {
        foreach (Truck truck in Vehicles.OfType<Truck>())
        {
            if (truck.Name.Contains(nameString))
            {
                vehicleNames += truck.ToString();
            }
        }            
    }

    if (vehicleNames == "")
    {
        return "No vehicles found";
    }
    else
    {
        return vehicleNames;
    }
}

Hope this helps.

C# - How To Check Object Type Using If Statement

1 Answers1