Math.Round Method (Decimal, Int32)
Updated: March 2012
Rounds a decimal value to a specified number of fractional digits.
Assembly: mscorlib (in mscorlib.dll)
- Type: System.Decimal
A decimal number to be rounded.
- Type: System.Int32
The number of decimal places in the return value.
Return ValueType: System.Decimal
The number nearest to d that contains a number of fractional digits equal to decimals.
The decimals parameter specifies the number of fractional digits in the return value and ranges from 0 to 28. If decimals is zero, an integer is returned.
This method is equivalent to calling the Round method with a mode argument of MidpointRounding.ToEven. If there is a single non-zero digit in d to the right of the decimals decimal position and its value is 5, the digit in the decimals position is rounded up if it is odd, or left unchanged if it is even. If d has fewer fractional digits than decimals, d is returned unchanged.
The behavior of this method follows IEEE Standard 754, section 4. This kind of rounding is sometimes called rounding to nearest, or banker's rounding. It minimizes rounding errors that result from consistently rounding a midpoint value in a single direction.
To control the type of rounding used by the method, call the Decimal.Round(Decimal, Int32, MidpointRounding) overload.
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.