mouse position + mousehook

Question

hi all,

I am trying to catch the mouse events all over the screen. I did a lot of researchs about that but unfortunatelly even the samples I found were in C and unfortunatelly I am using VB.NET 2005.

by saying that I managed to find one sample which works fine just on the current application's form.

but this is not what I want. I want to catch any mouse events that been made on the screen.

And I also want to turn on or off this facility. For example if I click button1 it will start and if I click button2 it will stop.

This following code is the one I managed to find. It is quite urgent and I am looking forward to see your helps.

Thanks

---

Imports System.Runtime.InteropServices

Public Class Form1

Private Structure MOUSEHOOKSTRUCT

Public pt As Point

Public hWnd As IntPtr

Public hitTest As Int32

Public extra As Int32

End Structure

Private _mouseHook As Int32 = 0

Private Const WH_MOUSE As Int32 = 7

Private Delegate Function CallBack(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MOUSEHOOKSTRUCT) As Int32

<MarshalAs(UnmanagedType.FunctionPtr)> Private _mouseProc As CallBack

Private Declare Function SetWindowsHookExW Lib "user32.dll" (ByVal idHook As Int32, ByVal HookProc As CallBack, ByVal hInstance As IntPtr, ByVal wParam As Int32) As Int32

Private Declare Function CallNextHookEx Lib "user32.dll" (ByVal idHook As Int32, ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MOUSEHOOKSTRUCT) As Int32

Private Declare Function GetCurrentThreadId Lib "kernel32.dll" () As Integer

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

If _mouseHook = 0 Then

_mouseProc = New CallBack(AddressOf MouseHookProc)

_mouseHook = SetWindowsHookExW(WH_MOUSE, _mouseProc, IntPtr.Zero, GetCurrentThreadId)

Dim err As Integer = Marshal.GetLastWin32Error

End If

End Sub

Private Shared Function MouseHookProc(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MOUSEHOOKSTRUCT) As Int32

Debug.Print("Message = {0}, x={1}, y={2}", wParam.ToInt32, lParam.pt.X, lParam.pt.Y)

Form1.Text = lParam.pt.X

Return CallNextHookEx(WH_MOUSE, nCode, wParam, lParam)

End Function

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

_mouseProc = New CallBack(AddressOf MouseHookProc)

_mouseHook = 0

End Sub

End Class

Answer 1

Hmm, looks familiar.  I updated the code to install a low-level global mouse hook:

Imports System.Runtime.InteropServices
Public Class Form1
  Private Structure MSLLHOOKSTRUCT
    Public pt As Point
    Public mouseData As Int32
    Public flags As Int32
    Public time As Int32
    Public extra As IntPtr
  End Structure

  Private _mouseHook As IntPtr
  Private Const WH_MOUSE_LL As Int32 = 14
  Private Delegate Function CallBack(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
  <MarshalAs(UnmanagedType.FunctionPtr)> Private _mouseProc As CallBack
  Private Declare Function SetWindowsHookExW Lib "user32.dll" (ByVal idHook As Int32, ByVal HookProc As CallBack, ByVal hInstance As IntPtr, ByVal wParam As Int32) As IntPtr
  Private Declare Function UnhookWindowsHookEx Lib "user32.dll" (ByVal hook As IntPtr) As Boolean
  Private Declare Function CallNextHookEx Lib "user32.dll" (ByVal idHook As Int32, ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
  Private Declare Function GetCurrentThreadId Lib "kernel32.dll" () As Integer
  Private Declare Function GetModuleHandleW Lib "kernel32.dll" (ByVal fakezero As IntPtr) As IntPtr


  Public Function InstallHook() As Boolean
    If _mouseHook = IntPtr.Zero Then
      _mouseProc = New CallBack(AddressOf MouseHookProc)
      _mouseHook = SetWindowsHookExW(WH_MOUSE_LL, _mouseProc, GetModuleHandleW(IntPtr.Zero), 0)
    End If
    Return _mouseHook <> IntPtr.Zero
  End Function

  Public Sub RemoveHook()
    If _mouseHook = IntPtr.Zero Then Return
    UnhookWindowsHookEx(_mouseHook)
    _mouseHook = IntPtr.Zero
  End Sub

  Private Shared Function MouseHookProc(ByVal nCode As Int32, ByVal wParam As IntPtr, ByRef lParam As MSLLHOOKSTRUCT) As Int32
    Debug.Print("Message = {0}, x={1}, y={2}", wParam.ToInt32, lParam.pt.X, lParam.pt.Y)
    Form1.Text = CStr(lParam.pt.X)
    Return CallNextHookEx(WH_MOUSE_LL, nCode, wParam, lParam)
  End Function

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
    InstallHook()
  End Sub

  Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
    RemoveHook()
  End Sub
End Class

Answer 2

hi nobugz

thank you ever so much. you are a lifesaver. thanks a lot.

Answer 3

Hi nobugz,

I have some what different requirement.

I have two application(Win32 exe). One application contains a button on it  & second application have many controls on it.

On click of button I  need my mouse pointer  should move to second application & highlight a control within it.

So how to move the mouse from one window to other window .

 

Any help appreciated

Yogesh