How to round off if the value is equal to 0.7 up in c#?

Question

I want to round off decimal if the value is 0.7 greater

Sample:

decimal rate = 3.7
decimal roundoff = 4 

decimal rate2 = 3.6
decimal roundoff2 = 3.6 //remain value coz its below 0.7

how can i do that in c#?

Answer 1

You can use modulus to calculate the remainder:

decimal d = rate % 1 >= .7m ? Math.Ceiling(rate) : rate;

You could use this for negative values:

return rate >= 0
       ? (rate % 1 >= .7m ? Math.Ceiling(rate) : rate) 
       : (Math.Abs(rate % 1) >= .3m ? Math.Floor(rate) : rate);

Answer 2

Purely because I couldn't resist trying a mathematical equivalent:

rate + (int)((rate % 1) / 0.7m) * (1 - Math.Abs(rate % 1));

Just can't get rid of the Math.Abs yet to make if completely without calls. If only positive numbers are used, the math.abs can be omitted as is.