What is Math.Round() in C#?
C# has a built-in Math class which provides useful mathematical functions and operations. The class has the Round() function, which is used to round a value to the nearest integer or to the specified number of fractional digits.
Variants
Round (Decimal)
This variant rounds a decimal param to a nearest integer, and rounds the midpoint to the nearest even number. It returns a decimal type number.
Syntax
public static decimal Round (decimal param);
where param is a decimal type input number to be rounded.
Round(Double)
It rounds a double-precision floating-point param to the nearest integer, and rounds the midpoint to the nearest even number. It returns a double type number.
Syntax
public static double Round (double param);
where:
paramis a double type input number to be rounded.
Round (Decimal, Int32)
This variant rounds a decimal param to a specified number of fractional digits, and rounds the midpoint to the nearest even number. It returns a decimal type number.
Syntax
public static decimal Round (decimal param, int digits);
where:
-
paramis a decimal type input number to be rounded. -
digitsis an Int32 type input number that specifies the number of decimal places in the output.
Round (Double, Int32)
This variant rounds a double-precision floating-point param to a specified number of fractional digits, and rounds the midpoint to the nearest even number. It returns a double type number.
Syntax
public static double Round (double param, int digits);
where:
-
paramis a double type input number to be rounded. -
digitsis an Int32 type input number that specifies the number of decimal places in the output.
Round (Decimal, MidpointRounding)
This variant rounds a decimal param to an integer according to the specified rounding convention. It returns a decimal type number.
Syntax
public static decimal Round (decimal param, MidpointRounding type);
where:
-
paramis a decimal type input number to be rounded. -
typespecifies the rounding strategy to be used.
Round (Double, MidpointRounding)
This variant rounds a double-precision floating-point param to an integer according to the specified rounding convention. It returns a double type number.
Syntax
public static double Round (double param, MidpointRounding type);
where:
-
paramis a double type input number to be rounded. -
typespecifies the rounding strategy to be used.
-
Round (Decimal, Int32, MidpointRounding)
It rounds a decimalparamto a specified number of fractional digits according to the specified rounding convention. It returns a decimal type number.
Syntax
public static decimal Round (decimal param, int digits, MidpointRounding type);
where:
-
paramis a decimal type input number to be rounded. -
digitsis an Int32 type input number that specifies the number of decimal places in the output. -
typespecifies the rounding strategy to be used.
Round (Double, Int32, MidpointRounding)
This rounds a double-precision floating-point param to a specified number of fractional digits according to the specified rounding convention. It returns a double type number.
Syntax
public static double Round (double param, int digits, MidpointRounding type);
where:
-
paramis a double type input number to be rounded. -
digitsis an Int32 type input number that specifies the number of decimal places in the output. -
typespecifies the rounding strategy to be used.
If
paramhas fewer fractional digits thandigits, thenparamis returned unchanged.
MidpointRounding methods
- ToEven: Rounding strategy towards the nearest even number.
- AwayFromZero: Rouding strategy towards the nearest number that’s away from zero.
- ToZero: Rounding strategy towards zero when result is closest to and no greater in magnitude than the infinitely precise result.
- ToNegativeInfinity: Downward-directed rounding strategy when result is closest to and no greater than the infinitely precise result.
- ToPositiveInfinity: Upwards-directed rounding strategy when result is closest to and no less than the infinitely precise result.
Code
using System;class Educative{static void Main(){System.Console.WriteLine(Math.Round(10.2563, 2));System.Console.WriteLine(Math.Round(10.8, 0, MidpointRounding.ToEven));System.Console.WriteLine(Math.Round(10.8, MidpointRounding.AwayFromZero));System.Console.WriteLine(Math.Round(10.6));}}
