I have a set of calls I want to make but the return values from the
windows API calls are incorrect.  What am I doing wrong?

   Public Structure RECT
        Dim Left As Long
        Dim Top As Long
        Dim Right As Long
        Dim Bottom As Long
    End Structure

    Public Declare Auto Function FindWindowEx Lib "user32" (ByVal
hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2
As String) As Long
    Public Declare Auto Function SendMessage Lib "user32" (ByVal hwnd
As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As
Long) As Long
    Public Declare Auto Function GetClientRect Lib "user32" (ByVal
hwnd As Long, ByVal lpRect As RECT) As Long

    Public Sub ClearSystemTray()

        Dim hTaskbar As Long
        Dim hTray As Long
        Dim rcTray As RECT
        Dim X As Long

        hTaskbar = FindWindowEx(0, 0, "Shell_TrayWnd", vbNullString)
        If hTaskbar Then
            hTray = FindWindowEx(hTaskbar, 0, "TrayNotifyWnd",
vbNullString)
            If hTray Then
                GetClientRect(hTray, rcTray)
                For X = 0 To rcTray.Right Step 8
                    SendMessage(hTray, WM_MOUSEMOVE, 0, &H80000 + X)
                Next
            End If
        End If

    End Sub

hTaskbar comes back as -5060775650092252192 not 0 as it should if it
fails.

Thanks
Jeff

API defines are incorrect, try changing Long to Int32 and String to
stringbuilder (if they need to me modified by the API) look at MSDN about
interopServices...

HTH
Corrado

Jeff,

Looks like Corrado has pointed you in the right direction.  Let us know if
you need anything further.

 Thank You,
 Dale Roberson
 Microsoft Developer Support

 This posting is provided "AS IS" with no warranties, and confers no rights.
 You assume all risk for your use. ? 2001 Microsoft Corporation. All rights
reserved.

I have the FindWindowEx, GetClientRect, and CopyMemory API calls to
work.  But I can't seem to find the proper syntax for SendMessage.  

This is what the API text viewer says.

Public Declare Function SendMessage Lib "user32" Alias "SendMessageA"
(ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam
As Any) As Long

This is what I tried.

Public Declare Function SendMessage Lib "user32" Alias "SendMessageA"
(ByVal hwnd As Int32, ByVal wMsg As Int32, ByVal wParam As Int32,
ByVal lParam As Int32) As Int32

But no luck.  I'm watching a process with Spy++ and trying to send a
mouse move to it.  Heres my call.

For X = 0 To rcTray.right
                    intMouseMove = MAKELONG(X, 10)
                    intReturn = SendMessage(hTray, WM_MOUSEMOVE, 0,
intMouseMove)

                Next

Any help would be great.

Thanks

Jeff

Looks like the declaration should work.  Are you getting a return code of 0?

 Thank You,
 Dale Roberson
 Microsoft Developer Support

 This posting is provided "AS IS" with no warranties, and confers no rights.
 You assume all risk for your use. ? 2001 Microsoft Corporation. All rights
reserved.

Yes the return value is zero.  But Spy++ shows no messages going to
that process.
 But I get a return of 0 even if I change the declaration around some.
I've tried experimenting with byref's and different types... All have
given a return of 0 with no message going where it should.

Jeff

Be careful about spy++.  I hooked the windows message processor to see if
the message was being sent and it is.  Here is what I wrote.

Create a form with a button.  Place the following code in the form.

    Dim catchmessage As Boolean = False

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click
        Dim x As Integer
        Dim mousepoint As Integer
        mousepoint = &H1000 Or &H20000000 'this is a bogus number I just
threw in for arguments sake.
        'It evaluates to 536875008 which you can see in the locals window
when you run the app

        catchmessage = True
        x = SendMessage(Me.Handle.ToInt32, WM_MOUSEMOVE, 0, mousepoint)
        catchmessage = False
    End Sub

    Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
        If catchmessage = True Then
            If m.Msg = WM_MOUSEMOVE Then
                MessageBox.Show(m.Msg.ToString & vbCrLf & m.LParam.ToString)
            End If
        End If
        MyBase.WndProc(m)
    End Sub

Create a module and add the following code.

    Public Declare Function SendMessage Lib "user32" _
    Alias "SendMessageA" (ByVal hwnd As Integer, _
    ByVal wMsg As Integer, ByVal wParam As Integer, _
    ByVal lParam As Integer) As Integer

    Public Const WM_MOUSEMOVE = &H200

The mouse doesn't actually move.  I don't have it all set up correctly to
handle this, I just want to see the message get to the window proc.

 Thank You,
 Dale Roberson
 Microsoft Developer Support

 This posting is provided "AS IS" with no warranties, and confers no rights.
 You assume all risk for your use. ? 2001 Microsoft Corporation. All rights
reserved.

I got it working... I found a sub window for the System Tray and
updated my code to use that as a target.  I now have code to clear any
dead icons from the system tray.  I wouldn't mind a critique of the
code.  Code Follows:

    <StructLayout(LayoutKind.Explicit)> Public Structure Rect
        <FieldOffset(0)> Public left As Integer
        <FieldOffset(4)> Public top As Integer
        <FieldOffset(8)> Public right As Integer
        <FieldOffset(12)> Public bottom As Integer
    End Structure

    Public Declare Auto Function FindWindowEx Lib "user32" (ByVal
hWnd1 As Int32, ByVal hWnd2 As Int32, ByVal lpsz1 As String, ByVal
lpsz2 As String) As Int32
    Public Declare Auto Function GetClientRect Lib "user32" (ByVal
hwnd As Int32, ByRef lpRect As Rect) As Int32
    Public Declare Auto Function PostMessage Lib "user32" (ByVal hwnd
As Int32, ByVal wMsg As Int32, ByVal wParam As Int32, ByVal lParam As
Int32) As Int32
    Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory"
(ByRef dest As Int16, ByRef src As Int32, ByVal length As Int32)

  Public Function LoWord(ByVal dwValue As Long) As Int16

        CopyMemory(LoWord, dwValue, 2)

    End Function

    Public Function MAKELONG(ByVal wLow As Long, ByVal wHigh As Long)
As Long

        MAKELONG = LoWord(wLow) Or (&H10000 * LoWord(wHigh))

    End Function

    Public Sub ClearSystemTray()

        Dim hTaskbar As Long
        Dim hTray As Long
        Dim hToolBar As Long
        Dim rcTray As Rect
        Dim X As Long
        Dim Y As Long
        Dim intMouseMove As Int32

        hTaskbar = FindWindowEx(0, 0, "Shell_TrayWnd", vbNullString)
        If hTaskbar Then
            hTray = FindWindowEx(hTaskbar, 0, "TrayNotifyWnd",
vbNullString)
            If hTray Then
                hToolBar = FindWindowEx(hTray, 0, "ToolbarWindow32",
vbNullString)
                If hToolBar Then
                    GetClientRect(hToolBar, rcTray)
                    For Y = 10 To rcTray.bottom Step 10
                        For X = 0 To rcTray.right Step 8
                            intMouseMove = MAKELONG(X, Y)
                            PostMessage(hToolBar, WM_MOUSEMOVE, 0,
intMouseMove)
                        Next
                    Next
                End If
            End If
        End If
    End Sub

Thanks for the help

Jeff Perrin