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

This works, I just tested it;

double a = 13.3;
var rn  =  a % 0.5 == 0 ? 1 : 0;
Math.Round(a, rn);