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UIntPtr.Subtraction(UIntPtr, Int32) Operator

  • Reference

Definition

Namespace:
System
Assembly:
System.Runtime.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
UIntPtr.cs
Source:
UIntPtr.cs
Source:
UIntPtr.cs

Subtracts an offset from an unsigned integer.

public:
 static UIntPtr operator -(UIntPtr pointer, int offset);
public static UIntPtr operator - (UIntPtr pointer, int offset);
static member ( - ) : unativeint * int -> unativeint
Public Shared Operator - (pointer As UIntPtr, offset As Integer) As UIntPtr

Parameters

pointer
UIntPtr

unativeint

The unsigned integer to subtract the offset from.

offset
Int32

The offset to subtract.

Returns

UIntPtr

unativeint

A new unsigned integer that reflects the subtraction of offset from pointer.

Remarks

The Subtraction method defines the subtraction operation for UIntPtr objects. It enables code such as the following.

int[] arr = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
UIntPtr ptr = (UIntPtr) arr[arr.GetUpperBound(0)];
for (int ctr = 0; ctr <= arr.GetUpperBound(0); ctr++)
{
   UIntPtr newPtr = ptr - ctr;
   Console.Write("{0}   ", newPtr);
}

let arr = [| 1; 2; 3; 4; 5; 6; 7; 8; 9; 10 |]
let ptr = UIntPtr(uint arr[arr.GetUpperBound 0])
for i = 0 to arr.GetUpperBound 0 do
    let newPtr = ptr - UIntPtr(uint i)
    printf $"{newPtr}   "

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

Languages that do not support custom operators can call the Subtract method instead.

The subtraction operation does not throw an exception if the result is too small to represent as an unsigned integer in the executing process. Instead, it is performed in an unchecked context.

In C# starting from version 11 and when targeting the .NET 7 or later runtime, this API is only accessible via reflection. The subtraction operator is directly recognized by the language and will follow the normal language behavior for subtraction operations, including overflowing in a checked context if the result is too small to represent.

Applies to

See also