Imports System.Runtime.InteropServices
Public Delegate Function CallBack( _
    ByVal nCode As Integer, _
    ByVal wParam As IntPtr, _
    ByVal lParam As IntPtr) As Integer

Public Class Form1

    'For other hook types, obtain these values from Winuser.h in Microsoft SDK.
    Dim WH_JOURNALRECORD As Integer = 0
    Dim WH_JOURNALPLAYBACK As Integer = 1
    Dim WH_KEYBOARD As Integer = 2
    Dim WH_GETMESSAGE As Integer = 3
    Dim WH_CALLWNDPROC As Integer = 4
    Dim WH_CBT As Integer = 5
    Dim WH_SYSMSGFILTER As Integer = 6
    Dim WH_MOUSE As Integer = 7
    Dim WH_HARDWARE As Integer = 8
    Dim WH_DEBUG As Integer = 9
    Dim WH_SHELL As Integer = 10
    Dim WH_FOREGROUNDIDLE As Integer = 11
    Dim WH_CALLWNDPROCRET As Integer = 12
    Dim WH_KEYBOARD_LL As Integer = 13
    Dim WH_MOUSE_LL As Integer = 14
    Shared hHook As Integer = 0

    'Keep the reference so that the delegate is not garbage collected.
    Private hookproc As CallBack

    'Import for the SetWindowsHookEx function.
    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Public Overloads Shared Function SetWindowsHookEx _
          (ByVal idHook As Integer, ByVal HookProc As CallBack, _
           ByVal hInstance As IntPtr, ByVal wParam As Integer) As Integer
    End Function

    'Import for the CallNextHookEx function.
    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Public Overloads Shared Function CallNextHookEx _
          (ByVal idHook As Integer, ByVal nCode As Integer, _
           ByVal wParam As IntPtr, ByVal lParam As IntPtr) As Integer
    End Function
    'Import for the UnhookWindowsHookEx function.
    <DllImport("User32.dll", CharSet:=CharSet.Auto, CallingConvention:=CallingConvention.StdCall)> _
    Public Overloads Shared Function UnhookWindowsHookEx _
              (ByVal idHook As Integer) As Boolean
    End Function

    'Point structure declaration.
    <StructLayout(LayoutKind.Sequential)> Public Structure Point
        Public x As Integer
        Public y As Integer
    End Structure

    'MouseHookStruct structure declaration.
    <StructLayout(LayoutKind.Sequential)> Public Structure MouseHookStruct
        Public pt As Point
        Public hwnd As Integer
        Public wHitTestCode As Integer
        Public dwExtraInfo As Integer
    End Structure

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.RichTextBox1.AppendText("[" & Now & "] START LOGGING" & vbCrLf)
        If hHook.Equals(0) Then
            hookproc = AddressOf MouseHookProc
            hHook = SetWindowsHookEx(WH_MOUSE, _
                                     hookproc, _
                                     IntPtr.Zero, _
AppDomain.GetCurrentThreadId())
            If hHook.Equals(0) Then
                Me.RichTextBox1.AppendText("SetWindowsHookEx Failed")
                Return
            End If
        Else
            Dim ret As Boolean = UnhookWindowsHookEx(hHook)

            If ret.Equals(False) Then
                Me.RichTextBox1.AppendText("UnhookWindowsHookEx Failed")
                Return
            Else
                hHook = 0
            End If
        End If

    End Sub

    Private Function FocusChanged(ByVal oldhwnd As Integer, ByVal oldpid As Integer, ByVal newhwnd As Integer, ByVal newpid As Integer) As Boolean

        Return True
    End Function
    Public Shared Function MouseHookProc( _
    ByVal nCode As Integer, _
    ByVal wParam As IntPtr, _
    ByVal lParam As IntPtr) As Integer
        Dim MyMouseHookStruct As New MouseHookStruct()

        If (nCode < 0) Then
            Return CallNextHookEx(hHook, nCode, wParam, lParam)
        End If

        MyMouseHookStruct = CType(Marshal.PtrToStructure(lParam, MyMouseHookStruct.GetType()), MouseHookStruct)

        Dim tempForm As Form
        tempForm = Form.ActiveForm()

        Dim strCaption As String
        strCaption = "x = " & MyMouseHookStruct.pt.x & " y = " & MyMouseHookStruct.pt.y

        tempForm.Text = strCaption
        Return CallNextHookEx(hHook, nCode, wParam, lParam)

    End Function
End Class