Decimal.Round Method
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Rounds a Decimal value to a specified number of decimal places.
Assembly: mscorlib (in mscorlib.dll)
Parameters
- d
- Type: System.Decimal
A Decimal value to round.
- decimals
- Type: System.Int32
A value from 0 to 28 that specifies the number of decimal places to round to.
Return Value
Type: System.DecimalThe Decimal number equivalent to d rounded to decimals number of decimal places.
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | decimals is not a value from 0 to 28. |
When d is exactly halfway between two rounded values, the result is the rounded value that has an even digit in the far right decimal position. For example, when rounded to two decimals, the value 2.345 becomes 2.34 and the value 2.355 becomes 2.36. This process is known as rounding toward even, or rounding to nearest.
The following code example rounds several Decimal values to a specified number of decimal places using the Round method.
// Example of the decimal.Round method. using System; class Example { const string dataFmt = "{0,26}{1,8}{2,26}"; // Display decimal.Round parameters and the result. public static void ShowDecimalRound(System.Windows.Controls.TextBlock outputBlock, decimal Argument, int Digits) { decimal rounded = decimal.Round(Argument, Digits); outputBlock.Text += String.Format(dataFmt, Argument, Digits, rounded) + "\n"; } public static void Demo(System.Windows.Controls.TextBlock outputBlock) { outputBlock.Text += "This example of the " + "decimal.Round( decimal, Integer ) \n" + "method generates the following output.\n" + "\n"; outputBlock.Text += String.Format(dataFmt, "Argument", "Digits", "Result") + "\n"; outputBlock.Text += String.Format(dataFmt, "--------", "------", "------") + "\n"; // Create pairs of decimal objects. ShowDecimalRound(outputBlock, 1.45M, 1); ShowDecimalRound(outputBlock, 1.55M, 1); ShowDecimalRound(outputBlock, 123.456789M, 4); ShowDecimalRound(outputBlock, 123.456789M, 6); ShowDecimalRound(outputBlock, 123.456789M, 8); ShowDecimalRound(outputBlock, -123.456M, 0); ShowDecimalRound(outputBlock, new decimal(1230000000, 0, 0, true, 7), 3); ShowDecimalRound(outputBlock, new decimal(1230000000, 0, 0, true, 7), 11); ShowDecimalRound(outputBlock, -9999999999.9999999999M, 9); ShowDecimalRound(outputBlock, -9999999999.9999999999M, 10); } } /* This example of the decimal.Round( decimal, Integer ) method generates the following output. Argument Digits Result -------- ------ ------ 1.45 1 1.4 1.55 1 1.6 123.456789 4 123.4568 123.456789 6 123.456789 123.456789 8 123.456789 -123.456 0 -123 -123.0000000 3 -123.000 -123.0000000 11 -123.0000000 -9999999999.9999999999 9 -10000000000.000000000 -9999999999.9999999999 10 -9999999999.9999999999 */