VB.Net: Reading NumLock status, even if the App doesn't have focus

Hi,
I need to read the NumLock status in VB.net.
After some Googling I found the following Class:
Public Class KeyState

  Declare Function GetKeyboardState Lib "user32" Alias "GetKeyboardState" (ByVal pbKeyState() As Byte) As Long
  Private KeyCode As Integer

  Public Sub New(ByVal keycode As Integer)
    Me.KeyCode = keycode
  End Sub

  Public Function KeyState() As Boolean
    Dim state(256) As Byte
    GetKeyboardState(state)
    Return (iif(state(Me.KeyCode) = 1, True, False))
  End Function

End Class

This works fine if the App has focus, but does not read the key correctly if another App as focus.

Is there a way to do this?

Thanks,

Richard
LVL 1
rpmAsked:
Who is Participating?
 
nffvrxqgrcfqvvcCommented:
You can use GetKeyState http://msdn.microsoft.com/en-us/library/windows/desktop/ms646301(v=VS.85).aspx
Public Class Form1
    
    Private Declare Auto Function GetKeyState Lib "User32.dll" (ByVal nVirtKey As Integer) As Short

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        '   keyBits(0)= ' low-bit
        '   keyBits(1)= ' high-bit
        '   If the low-order bit is 1, the key is toggled. A key, such as the CAPS LOCK key, is toggled if it is turned on. 
        '   The key is off and untoggled if the low-order bit is 0. A toggle key's indicator light (if any) on the keyboard 
        '   will be on when the key is toggled, and off when the key is untoggled.

        Dim keyBits() As Byte = BitConverter.GetBytes(GetKeyState(Keys.NumLock))
        If keyBits(0) = 1 Then
            Debug.Print("Numlock ON")
        End If

    End Sub
End Class

Open in new window

0
 
rpmAuthor Commented:
Great, thanks! That does the trick!

Richard
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.