Tasten sperren

Tasten sperren
Ich habe gegooglet unt nichts gefunden.
Wie kann man sagen das wenn das programm geöffnet ist das z.b die taste "A" gesperrt ist?

Müsste das hier sein bin mir aber nicht sicher

Code:

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Public Class Form1
 
  ' benötigte API-Deklarationen
  Private Declare Function GetAsyncKeyState Lib "user32" ( _
    ByVal vKey As Integer) As Short
  Private Declare Sub keybd_event Lib "user32" ( _
    ByVal bVk As Byte, _
    ByVal bScan As Byte, _
    ByVal dwFlags As Integer, _
    ByVal dwExtraInfo As Integer)
 
  Const KEYEVENTF_KEYUP = &H2
  Const VK_ESCAPE = &H1B
  Const VK_LWIN = &H5B
  Const VK_RWIN = &H5C
 
  ' Timer
  Dim WithEvents oTimer As Timer
  Private Sub Form1_Load(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles MyBase.Load
 
    ' Timer-Intervall einstellen und starten
    oTimer = New Timer
    oTimer.Interval = 10
    oTimer.Start()
  End Sub
  Private Sub Form1_FormClosing(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
 
    ' Timer stoppen
    oTimer.Stop()
  End Sub
  Private Sub oTimer_Tick(ByVal sender As Object, _
    ByVal e As System.EventArgs) Handles oTimer.Tick
 
    If CBool(GetAsyncKeyState(VK_LWIN) And 1) Or _
      CBool(GetAsyncKeyState(VK_RWIN) And 1) Then
 
      ' Wenn Windowstaste gedrückt, Escapetaste drücken...
      Call keybd_event(VK_ESCAPE, 0, 0, 0)
 
      ' ... und wieder loslassen
      Call keybd_event(VK_ESCAPE, 0, KEYEVENTF_KEYUP, 0)
    End If
  End Sub
End Class

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