.NET Class for Caps, Num & Scroll Lock Control - Visual Basic , VB.NET

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.NET Class for Caps, Num & Scroll Lock Control
Author: Tonester
Website: http://www.dataaspects.com.au
Submitted: 11/1/2005
Version: VB.NET 2003
Compatibility: VB.NET 2003, VB.NET 2005
Category: Windows API
Views: 27549
This class will give you complete control over the CAPSLOCK, NUMLOCK and SCOLLLOCK keys. It is basically a wrapped class for a small part of the Win32 API relating to keyboard control. This code was based upon code supplied by JD.
Declarations:
'Declare these in a module somewhere Public Const VK_NUMLOCK As Short = &H90S Public Const VK_SCROLL As Short = &H91S Public Const VK_CAPITAL As Short = &H14S Public Const KEYEVENTF_EXTENDEDKEY As Short = &H1S Public Const KEYEVENTF_KEYUP As Short = &H2S Public Const VER_PLATFORM_WIN32_NT As Short = 2 Public Const VER_PLATFORM_WIN32_WINDOWS As Short = 1
Code:
'Copy this code into a new VB file Namespace KeyboardFunctions Public Enum KeyToggleStatus As Integer StatusOn = 0 StatusOff End Enum Public Enum ToggleKey As Integer CapsLock = 0 NumLock ScrollLock End Enum Public Class ToggleKeyControl Private Structure OSVERSIONINFO Dim dwOSVersionInfoSize As Integer Dim dwMajorVersion As Integer Dim dwMinorVersion As Integer Dim dwBuildNumber As Integer Dim dwPlatformId As Integer <VBFixedString(128), System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst:=128)> Public szCSDVersion As String ' Maintenance string for PSS usage End Structure ' API declarations: 'UPGRADE_WARNING: Structure OSVERSIONINFO may require marshalling attributes to be passed as an argument in this Declare statement. Click for more: 'ms-help://MS.VSCC.2003/commoner/redir/redirect.htm?keyword="vbup1050"' Private Declare Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" (ByRef lpVersionInformation As OSVERSIONINFO) As Integer Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Integer, ByVal dwExtraInfo As Integer) Private Declare Function GetKeyboardState Lib "user32" (ByRef pbKeyState As Byte) As Integer Private Declare Function SetKeyboardState Lib "user32" (ByRef lppbKeyState As Byte) As Integer Public Shared Sub SetLock(ByVal targetKey As ToggleKey, ByVal status As KeyToggleStatus) Dim o As OSVERSIONINFO o.dwOSVersionInfoSize = Len(o) GetVersionEx(o) Dim keys(255) As Byte Dim index As Short GetKeyboardState(keys(0)) If GetLockStatus(targetKey) = status Then 'Nothing to do as the required status is already set Else Select Case targetKey Case ToggleKey.CapsLock : index = VK_CAPITAL Case ToggleKey.NumLock : index = VK_NUMLOCK Case ToggleKey.ScrollLock : index = VK_SCROLL End Select If status = KeyToggleStatus.StatusOn Then If o.dwPlatformId = VER_PLATFORM_WIN32_WINDOWS Then '=== Win95/98 keys(index) = 1 SetKeyboardState(keys(0)) ElseIf o.dwPlatformId = VER_PLATFORM_WIN32_NT Then '=== WinNT 'Simulate Key Press keybd_event(index, &H45S, KEYEVENTF_EXTENDEDKEY Or 0, 0) 'Simulate Key Release keybd_event(index, &H45S, KEYEVENTF_EXTENDEDKEY Or KEYEVENTF_KEYUP, 0) End If Else If o.dwPlatformId = VER_PLATFORM_WIN32_WINDOWS Then '=== Win95/98 keys(index) = 0 SetKeyboardState(keys(0)) ElseIf o.dwPlatformId = VER_PLATFORM_WIN32_NT Then '=== WinNT 'Simulate Key Press keybd_event(index, &H45S, KEYEVENTF_EXTENDEDKEY Or 0, 0) 'Simulate Key Release keybd_event(index, &H45S, KEYEVENTF_EXTENDEDKEY Or KEYEVENTF_KEYUP, 0) End If End If End If End Sub Public Shared Function GetLockStatus(ByVal targetKey As ToggleKey) As KeyboardFunctions.KeyToggleStatus Dim LockState As Boolean = False Dim keys(255) As Byte GetKeyboardState(keys(0)) Select Case targetKey Case ToggleKey.CapsLock : LockState = keys(VK_CAPITAL) Case ToggleKey.NumLock : LockState = keys(VK_NUMLOCK) Case ToggleKey.ScrollLock : LockState = keys(VK_SCROLL) End Select Return ToKeyToggleStatus(LockState) End Function Public Shared Function ToKeyToggleStatus(ByVal value As Boolean) As KeyToggleStatus If value Then Return KeyToggleStatus.StatusOn Else Return KeyToggleStatus.StatusOff End If End Function End Class End Namespace