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UIntPtr.Subtract Method

Subtracts an offset from the value of an unsigned pointer.

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

'Declaration
Public Shared Function Subtract ( _
	pointer As UIntPtr, _
	offset As Integer _
) As UIntPtr

Parameters

pointer
Type: System.UIntPtr

The unsigned pointer to subtract the offset from.

offset
Type: System.Int32

The offset to subtract.

Return Value

Type: System.UIntPtr
A new unsigned pointer that reflects the subtraction of offset from pointer.

The Subtract method does not throw an exception if the result is too small to represent as a pointer on the specified platform. Instead, the subtraction operation is performed in an unchecked context.

Languages that do not support operator overloading or custom operators can use this method to subtract an offset from the value of an unsigned pointer.

The following example instantiates an IntPtr object that points to the end of a ten-element array, and then calls the Subtract method to iterate the elements in the array in reverse order.

Module Example
   Public Sub Main()
      Dim arr() As Integer = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}
      Dim ptr As UIntPtr = CType(arr(arr.GetUpperBound(0)), UIntPtr)
      For ctr As Integer= 0 To arr.GetUpperBound(0)
         Dim newPtr As UIntPtr = UIntPtr.Subtract(ptr, ctr)
         Console.Write("{0}   ", newPtr)
      Next 
   End Sub 
End Module 
' The example displays the following output: 
'       10   9   8   7   6   5   4   3   2   1

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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