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Decimal.Decrement Operator

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Decrements the Decimal operand by one.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Shared Operator -- ( _
    d As Decimal _
) As Decimal
public static decimal operator --(
    decimal d
)

Parameters

Return Value

Type: System.Decimal
The value of d decremented by 1.

Exceptions

Exception Condition
OverflowException

The return value is less than MinValue or greater than MaxValue.

Examples

The following code example applies the Decrement operator to several Decimal values.

' Example of the Decimal increment, decrement, unary negation, and 
' unary plus operators.

Module Example

   ' Get the exception type name; remove the namespace prefix.
   Function GetExceptionType(ByVal ex As Exception) As String

      Dim exceptionType As String = ex.GetType().ToString()
      Return exceptionType.Substring( _
          exceptionType.LastIndexOf("."c) + 1)
   End Function

   ' Display the argument and the incremented and decremented values.
   Sub DecIncrDecrUnary(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal argument As Decimal)

      Dim toBeIncr As Decimal = argument
      Dim toBeDecr As Decimal = argument

      outputBlock.Text &= String.Format("{0,-36}{1}", "Decimal argument: ", _
          argument) & vbCrLf

      ' The op_Increment and op_Decrement operators must be 
      ' explicitly coded in Visual Basic.

      ' Catch the exception if the increment operator throws one.
      outputBlock.Text &= String.Format("{0,-36}", "Decimal.op_Increment( argument )")
      Try
         toBeIncr = Decimal.op_Increment(toBeIncr)
         outputBlock.Text &= String.Format("{0}", toBeIncr) & vbCrLf
      Catch ex As Exception
         outputBlock.Text &= String.Format("{0}", GetExceptionType(ex)) & vbCrLf
      End Try

      ' Catch the exception if the decrement operator throws one.
      outputBlock.Text &= String.Format("{0,-36}", "Decimal.op_Decrement( argument )")
      Try
         toBeDecr = Decimal.op_Decrement(toBeDecr)
         outputBlock.Text &= String.Format("{0}", toBeDecr) & vbCrLf
      Catch ex As Exception
         outputBlock.Text &= String.Format("{0}", GetExceptionType(ex)) & vbCrLf
      End Try

      outputBlock.Text &= vbCrLf
   End Sub

   Public Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      outputBlock.Text &= String.Format( _
          "This example of the Decimal increment, decrement, " & _
          "unary negation, " & vbCrLf & "and unary plus " & _
          "operators generates the following output. It " & vbCrLf & _
          "displays the results of the operators on several " & _
          "Decimal values." & vbCrLf) & vbCrLf

      ' Create objects to compare with the reference.
      DecIncrDecrUnary(outputBlock, 0.000000123D)
      DecIncrDecrUnary(outputBlock, New Decimal(123000000, 0, 0, False, 9))

      ' The op_UnaryNegation and op_UnaryPlus operators must be
      ' explicitly coded in Visual Basic. If unary + or - is used,
      ' other methods are called.
      DecIncrDecrUnary(outputBlock, Decimal.op_UnaryNegation( _
          New Decimal(123000000, 0, 0, False, 9)))
      DecIncrDecrUnary(outputBlock, Decimal.op_UnaryPlus(Decimal.MaxValue))
      DecIncrDecrUnary(outputBlock, Decimal.op_UnaryNegation(Decimal.MaxValue))
      DecIncrDecrUnary(outputBlock, Decimal.op_UnaryPlus( _
          7.5000000000000000000000000001D))
   End Sub
End Module

' This example of the Decimal increment, decrement, unary negation,
' and unary plus operators generates the following output. It
' displays the results of the operators on several Decimal values.
' 
' Decimal argument:                   0.000000123
' Decimal.op_Increment( argument )    1.000000123
' Decimal.op_Decrement( argument )    -0.999999877
' 
' Decimal argument:                   0.123000000
' Decimal.op_Increment( argument )    1.123000000
' Decimal.op_Decrement( argument )    -0.877000000
' 
' Decimal argument:                   -0.123000000
' Decimal.op_Increment( argument )    0.877000000
' Decimal.op_Decrement( argument )    -1.123000000
' 
' Decimal argument:                   79228162514264337593543950335
' Decimal.op_Increment( argument )    OverflowException
' Decimal.op_Decrement( argument )    79228162514264337593543950334
' 
' Decimal argument:                   -79228162514264337593543950335
' Decimal.op_Increment( argument )    -79228162514264337593543950334
' Decimal.op_Decrement( argument )    OverflowException
' 
' Decimal argument:                   7.5000000000000000000000000001
' Decimal.op_Increment( argument )    8.500000000000000000000000000
' Decimal.op_Decrement( argument )    6.5000000000000000000000000001
// Example of the decimal increment, decrement, unary negation, and 
// unary plus operators.
using System;

class Example
{
   // Get the exception type name; remove the namespace prefix.
   public static string GetExceptionType(Exception ex)
   {
      string exceptionType = ex.GetType().ToString();
      return exceptionType.Substring(
          exceptionType.LastIndexOf('.') + 1);
   }

   // Display the argument and the incremented and decremented values.
   public static void DecIncrDecrUnary(System.Windows.Controls.TextBlock outputBlock, decimal argument)
   {
      decimal toBeIncr = argument;
      decimal toBeDecr = argument;

      outputBlock.Text += String.Format("{0,-26}{1}", "decimal argument: ",
          argument) + "\n";

      // Catch the exception if the increment operator throws one.
      outputBlock.Text += String.Format("{0,-26}", "argument ++");
      try
      {
         toBeIncr++;
         outputBlock.Text += String.Format("{0}", toBeIncr) + "\n";
      }
      catch (Exception ex)
      {
         outputBlock.Text += String.Format("{0}", GetExceptionType(ex)) + "\n";
      }

      // Catch the exception if the decrement operator throws one.
      outputBlock.Text += String.Format("{0,-26}", "argument --");
      try
      {
         toBeDecr--;
         outputBlock.Text += String.Format("{0}", toBeDecr) + "\n";
      }
      catch (Exception ex)
      {
         outputBlock.Text += String.Format("{0}", GetExceptionType(ex)) + "\n";
      }

      outputBlock.Text += "\n";
   }

   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      outputBlock.Text += String.Format("This example of the decimal increment, " +
          "decrement, unary negation, \nand unary plus operators " +
          "generates the following output. It \ndisplays the " +
          "results of the operators on several decimal values.\n") + "\n";

      // Create objects to compare with the reference.
      DecIncrDecrUnary(outputBlock, 0.000000123M);
      DecIncrDecrUnary(outputBlock, new decimal(123000000, 0, 0, false, 9));
      DecIncrDecrUnary(outputBlock, -new decimal(123000000, 0, 0, false, 9));
      DecIncrDecrUnary(outputBlock, +decimal.MaxValue);
      DecIncrDecrUnary(outputBlock, -decimal.MaxValue);
      DecIncrDecrUnary(outputBlock, +7.5000000000000000000000000001M);
   }
}

/*
This example of the decimal increment, decrement, unary negation,
and unary plus operators generates the following output. It
displays the results of the operators on several decimal values.

decimal argument:         0.000000123
argument ++               1.000000123
argument --               -0.999999877

decimal argument:         0.123000000
argument ++               1.123000000
argument --               -0.877000000

decimal argument:         -0.123000000
argument ++               0.877000000
argument --               -1.123000000

decimal argument:         79228162514264337593543950335
argument ++               OverflowException
argument --               79228162514264337593543950334

decimal argument:         -79228162514264337593543950335
argument ++               -79228162514264337593543950334
argument --               OverflowException

decimal argument:         7.5000000000000000000000000001
argument ++               8.500000000000000000000000000
argument --               6.5000000000000000000000000001
*/

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.