Question

I have this two objects

    class RNB
    {
        public RNB(double roomRate, double roomDays)
        {
            RoomRate = roomRate;
            RoomDays = roomDays;
        }

        public double RoomRate { get; set; }
        public double RoomDays { get; set; }
        public const double BasicLimit = 100;
    }

    class HMS
    {
        public double Amount { get; set; }
        public const double BasicLimit = 200;
    }

And then I have this method:

    public static double ComputeBasicAmount(double basicLimit, Func<double> multiplier)
    {
        return basicLimit * multiplier();
    }

Sample usage:

    static void Main(string[] args)
    {
        RNB rnb = new RNB(100, 2);
        double result = ComputeBasicAmount(RNB.BasicLimit, () => rnb.RoomDays * rnb.RoomRate);
        Console.WriteLine("RNB Basic Amt: " + result.ToString());

        HMS hms = new HMS() { Amount = 1000 };
        result = ComputeBasicAmount(HMS.BasicLimit, () => hms.Amount);
        Console.WriteLine("HMS Basic Amt: " + result.ToString());

        Console.Read();
    }

The problem here, I Want to eliminate the passing of the BasicLimit because i think it looks redundant here. Is it possible to put the BasicLimit inside the ComputeBasicAmount method

Something like this..

 public static double ComputeBasicAmount<T>(Func<T, double> multiplier, T obj)
  {

      return obj.BasicLimit * multiplier();
  }

Thanks in advance guys…

PS: The basicLimit doesn’t have to be CONST

Answer 1

Yes you could, but you would have to check the type of obj first, since you can’t restrict the type parameter to be of a specific class.

This means you can’t define ComputeBasicAmount to only be called as ComputeBasicAmount<RNB> and ComputeBasicAmount<HMS>.

But, you could check if obj is either of the type RNB or HMS:

public static double ComputeBasicAmount<T>(Func<T, double> multiplier, T obj)
{
    var cObj1 = obj as RNB;
    if(cObj1!=null)
        return cObj1.BasicLimit * multiplier();

    var cObj2 = obj as HMS;
    if(cObj2 != null)
        return cObj1.BasicLimit * multiplier(); 

    return null; //Or throw an exception, e.g. argument exception
}