Rounding of nearest 0.5

Question

I want to be rounded off this way

13.1, round to 13.5
13.2, round to 13.5
13.3, round to 13.5
13.4, round to 13.5
13.5 = 13.5
13.6, round to 14.0
13.7, roun         


        

Answer 1

num = (num % 0.5 == 0 ? num : Math.Round(num));

works well for you solution heres the complete console program

static void Main(string[] args)
        {
            double[] a = new double[]{
                13.1,13.2,13.3D,13.4,13.5,13.6,13.7,13.8,13.9,13.58,13.49,13.55,
            };
            foreach (var b in a)
            {
                Console.WriteLine("{0}-{1}",b,b % 0.5 == 0 ? b : Math.Round(b));
            }
            Console.ReadKey();
        }

you simply would need to change 0.5 to some other number if the rounding requirement changes in future