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BitVector32.CreateMask Method (Int32)

Creates an additional mask following the specified mask in a series of masks that can be used to retrieve individual bits in a BitVector32 that is set up as bit flags.

Namespace:  System.Collections.Specialized
Assembly:  System (in System.dll)

Public Shared Function CreateMask ( _
	previous As Integer _
) As Integer


Type: System.Int32

The mask that indicates the previous bit flag.

Return Value

Type: System.Int32
A mask that isolates the bit flag following the one that previous points to in BitVector32.


previous indicates the last bit flag in the BitVector32.

Use CreateMask() to create the first mask in a series and CreateMask(int) for all subsequent masks.

Multiple masks can be created to refer to the same bit flag.

The resulting mask isolates only one bit flag in the BitVector32. You can combine masks using the bitwise OR operation to create a mask that isolates multiple bit flags in the BitVector32.

Using a mask on a BitVector32 that is set up as sections might cause unexpected results.

This method is an O(1) operation.

The following code example shows how to create and use masks.

Imports System
Imports System.Collections.Specialized

Public Class SamplesBitVector32

   Public Shared Sub Main()

      ' Creates and initializes a BitVector32 with all bit flags set to FALSE. 
      Dim myBV As New BitVector32(0)

      ' Creates masks to isolate each of the first five bit flags. 
      Dim myBit1 As Integer = BitVector32.CreateMask()
      Dim myBit2 As Integer = BitVector32.CreateMask(myBit1)
      Dim myBit3 As Integer = BitVector32.CreateMask(myBit2)
      Dim myBit4 As Integer = BitVector32.CreateMask(myBit3)
      Dim myBit5 As Integer = BitVector32.CreateMask(myBit4)
      Console.WriteLine("Initial:               " + ControlChars.Tab + "{0}", myBV.ToString())

      ' Sets the third bit to TRUE.
      myBV(myBit3) = True
      Console.WriteLine("myBit3 = TRUE          " + ControlChars.Tab + "{0}", myBV.ToString())

      ' Combines two masks to access multiple bits at a time.
      myBV((myBit4 + myBit5)) = True
      Console.WriteLine("myBit4 + myBit5 = TRUE " + ControlChars.Tab + "{0}", myBV.ToString())
      myBV((myBit1 Or myBit2)) = True
      Console.WriteLine("myBit1 | myBit2 = TRUE " + ControlChars.Tab + "{0}", myBV.ToString())

   End Sub 'Main 

End Class 'SamplesBitVector32

' This code produces the following output. 

' Initial:                BitVector32{00000000000000000000000000000000} 
' myBit3 = TRUE           BitVector32{00000000000000000000000000000100} 
' myBit4 + myBit5 = TRUE  BitVector32{00000000000000000000000000011100} 
' myBit1 | myBit2 = TRUE  BitVector32{00000000000000000000000000011111}

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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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