vb.net keyboard hook example

 Imports System.Runtime.InteropServices

Public Class Form1

    Private Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Integer, ByVal lpfn As KeyboardProc, ByVal hmod As IntPtr, ByVal dwThreadId As Integer) As IntPtr

    Private Declare Function CallNextHookEx Lib "user32" (ByVal hhk As IntPtr, ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

    Private Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hhk As IntPtr) As Boolean

    Private Delegate Function KeyboardProc(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

    Private Const WM_KEYDOWN As Integer = &H100

    Private Const WH_KEYBOARD_LL As Integer = 13

    Private hHook As IntPtr

    Private Function KeyboardProcHandler(ByVal nCode As Integer, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

        If nCode >= 0 AndAlso wParam = WM_KEYDOWN Then

            Dim vkCode As Integer = Marshal.ReadInt32(lParam)

            MessageBox.Show("Key Code: " & vkCode)

        End If

        Return CallNextHookEx(hHook, nCode, wParam, lParam)

    End Function

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

        hHook = SetWindowsHookEx(WH_KEYBOARD_LL, AddressOf KeyboardProcHandler, IntPtr.Zero, 0)

    End Sub

    Private Sub Form1_FormClosing(sender As Object, e As FormClosingEventArgs) Handles Me.FormClosing

        UnhookWindowsHookEx(hHook)

    End Sub

End Class