Round a decimal to the nearest quarter in C#

Is there a simple way in c# to round a decimal to the nearest quarter i.e. x.0, x.25, x.50 x.75 for example 0.21开发者_如何学JAVA would round to 0.25, 5.03 would round to 5.0

Thanks in advance for any help.

Multiply it by four, round it as you need to an integer, then divide it by four again:

x = Math.Round (x * 4, MidpointRounding.ToEven) / 4;

The various options for rounding, and their explanations, can be found in this excellent answer here :-)

Alternatively, you can use UltimateRoundingFunction given in this blog: http://rajputyh.blogspot.in/2014/09/the-ultimate-rounding-function.html

//amountToRound => input amount
//nearestOf => .25 if round to quater, 0.01 for rounding to 1 cent, 1 for rounding to $1
//fairness => btween 0 to 0.9999999___.
//            0 means floor and 0.99999... means ceiling. But for ceiling, I would recommend, Math.Ceiling
//            0.5 = Standard Rounding function. It will round up the border case. i.e. 1.5 to 2 and not 1.
//            0.4999999... non-standard rounding function. Where border case is rounded down. i.e. 1.5 to 1 and not 2.
//            0.75 means first 75% values will be rounded down, rest 25% value will be rounded up.
decimal UltimateRoundingFunction(decimal amountToRound, decimal nearstOf, decimal fairness)
{
    return Math.Floor(amountToRound / nearstOf + fairness) * nearstOf;
}

Call below for standard rounding. i.e. 1.125 will be rounded to 1.25

UltimateRoundingFunction(amountToRound, 0.25m, 0.5m);

Call below for rounding down border values. i.e. 1.125 will be rounded to 1.00

UltimateRoundingFunction(amountToRound, 0.25m, 0.4999999999999999m);

So called "Banker's Rounding" is not possible with UltimateRoundingFunction, you have to go with paxdiablo's answer for that support :)

An extension method based on this answer.

namespace j
{
    public static class MathHelpers
    {
        public static decimal RoundToNearestQuarter(this decimal x)
        {
            return Math.Round(x * 4, MidpointRounding.ToEven) / 4;
        }
    }
}