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IntPtr.Subtract Method

Subtracts an offset from the value of a pointer.

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

public static IntPtr Subtract(
	IntPtr pointer,
	int offset


Type: System.IntPtr
The pointer to subtract the offset from.
Type: System.Int32
The offset to subtract.

Return Value

Type: System.IntPtr
A new 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 a 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.

using System;

public class Example
   public static void Main()
      int[] arr = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
      IntPtr ptr = (IntPtr) arr[arr.GetUpperBound(0)];
      for (int ctr = 0; ctr <= arr.GetUpperBound(0); ctr++)
         IntPtr newPtr = IntPtr.Subtract(ptr, ctr);
         Console.Write("{0}   ", newPtr);
// The example displays the following output:
//       10   9   8   7   6   5   4   3   2   1

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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