Toggle(Turn On/Off) Caps Lock/Num Lock/Scroll Lock keys

[Deepak Sakpal]

Imports System.Runtime.InteropServices
 
Public Class Form2
 
    Private Declare Sub keybd_event Lib "user32" ( _
        ByVal bVk As Byte, _
        ByVal bScan As Byte, _
        ByVal dwFlags As Integer, _
        ByVal dwExtraInfo As Integer _
    )
 
    Private Const VK_CAPITAL As Integer = &H14
    Private Const KEYEVENTF_EXTENDEDKEY As Integer = &H1
    Private Const KEYEVENTF_KEYUP As Integer = &H2
 
    Private Sub Button1_Click( _
        ByVal sender As System.Object, _
        ByVal e As System.EventArgs _
    ) Handles Button1.Click
 
        ' Toggle CapsLock
 
        ' Simulate the Key Press
        keybd_event(VK_CAPITAL, &H45, KEYEVENTF_EXTENDEDKEY Or 0, 0)
        
        ' Simulate the Key Release
        keybd_event(VK_CAPITAL, &H45, KEYEVENTF_EXTENDEDKEY Or KEYEVENTF_KEYUP, 0)
    End Sub
 
End Class

You can use the above code to toggle NUM LOCK and SCROLL LOCK keys, you just need to replace VK_CAPITAL with appropriate constant variables of NUM LOCK and SCROLL LOCK keys. The constant variables of NUM LOCK and SCROLL LOCK keys are as below:

Private Const VK_NUMLOCK As Integer = &H90
Private Const VK_SCROLL As Integer = &H91