[RESOLVED] Keyboard hook giving error

[tropix100]

Trying to convert my home app from vb6 to .net but have a problem. I am using the code in the tut by Paul Kimmel but it is returning Err.LastDllError = 126.
I am using this code as posted on Win7 and VS2010.
KeyboardHandle is retuning 0 but Im not sure which part of it is the problem. There is a lot of new stuff there for me.

Public Sub HookKeyboard()
        callback = New KeyboardHookDelegate(AddressOf KeyboardCallback)
        KeyboardHandle = SetWindowsHookEx(WH_KEYBOARD_LL, callback, Marshal.GetHINSTANCE([Assembly].GetExecutingAssembly.GetModules()(0)).ToInt32, 0)
        Call CheckHooked()
    End Sub

Thanks for any help.

[.paul.]

have you set your target CPU = x86?

[.paul.]

also api declarations are different in vb6 than they are in vb.net
it would help if you posted your code

[tropix100]

hey .paul.
Thanks for ya time.
Stting the cpu?....I have no idea what you mean about that. NEVER heard of a need to set my cpu. Sorry for my ignorance but thats why Im here.
As I said in my origional...Its a direct copy of Paul Kimmels ...but here it is.

Imports System.Runtime.InteropServices
Imports System.Reflection
Imports System.Drawing
Imports System.Threading

Module Keyboard
    Public Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Integer) As Integer

    Public Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Integer, ByVal lpfn As KeyboardHookDelegate, ByVal hmod As Integer, ByVal dwThreadId As Integer) As Integer

    Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Integer) As Integer

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

    Public Structure KBDLLHOOKSTRUCT
        Public vkCode As Integer
        Public scanCode As Integer
        Public flags As Integer
        Public time As Integer
        Public dwExtraInfo As Integer
    End Structure

    ' Low-Level Keyboard Constants
    Private Const HC_ACTION As Integer = 0
    Private Const LLKHF_EXTENDED As Integer = &H1
    Private Const LLKHF_INJECTED As Integer = &H10
    Private Const LLKHF_ALTDOWN As Integer = &H20
    Private Const LLKHF_UP As Integer = &H80

    ' Virtual Keys
    Public Const VK_TAB = &H9
    Public Const VK_CONTROL = &H11
    Public Const VK_ESCAPE = &H1B
    Public Const VK_DELETE = &H2E

    Private Const WH_KEYBOARD_LL As Integer = 13&
    Public KeyboardHandle As Integer


    ' Implement this function to block as many
    ' key combinations as you'd like
    Public Function IsHooked(ByRef Hookstruct As KBDLLHOOKSTRUCT) As Boolean

        Debug.WriteLine("Hookstruct.vkCode: " & Hookstruct.vkCode)
        Debug.WriteLine(Hookstruct.vkCode = VK_ESCAPE)
        Debug.WriteLine(Hookstruct.vkCode = VK_TAB)

        If (Hookstruct.vkCode = VK_ESCAPE) And CBool(GetAsyncKeyState(VK_CONTROL) And &H8000) Then
            Call HookedState("Ctrl + Esc blocked")
            Return True
        End If

        If (Hookstruct.vkCode = VK_TAB) And CBool(Hookstruct.flags And LLKHF_ALTDOWN) Then
            Call HookedState("Alt + Tab blockd")
            Return True
        End If

        If (Hookstruct.vkCode = VK_ESCAPE) And CBool(Hookstruct.flags And LLKHF_ALTDOWN) Then
            Call HookedState("Alt + Escape blocked")
            Return True
        End If

        Return False
    End Function

    Private Sub HookedState(ByVal Text As String)
        Debug.WriteLine(Text)
    End Sub

    Public Function KeyboardCallback(ByVal Code As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer

        If (Code = HC_ACTION) Then
            Debug.WriteLine("Calling IsHooked")

            If (IsHooked(lParam)) Then
                Return 1
            End If

        End If

        Return CallNextHookEx(KeyboardHandle, Code, wParam, lParam)

    End Function


    Public Delegate Function KeyboardHookDelegate(ByVal Code As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer
    <MarshalAs(UnmanagedType.FunctionPtr)> Private callback As KeyboardHookDelegate

    Public Sub HookKeyboard()
        callback = New KeyboardHookDelegate(AddressOf KeyboardCallback)
        KeyboardHandle = SetWindowsHookEx(WH_KEYBOARD_LL, callback, Marshal.GetHINSTANCE([Assembly].GetExecutingAssembly.GetModules()(0)).ToInt32, 0)
        Call CheckHooked()
    End Sub

    Public Sub CheckHooked()
        If (Hooked()) Then
            Debug.WriteLine("Keyboard hooked")
        Else
            Debug.WriteLine("Keyboard hook failed: " & Err.LastDllError)
        End If
    End Sub

    Private Function Hooked()
        Hooked = KeyboardHandle <> 0
    End Function

    Public Sub UnhookKeyboard()
        If (Hooked()) Then
            Call UnhookWindowsHookEx(KeyboardHandle)
        End If
    End Sub

End Module

Is setting the target cpu a 2010 specific issue? What are the other options for this setting?

Your help is appreciated.

[.paul.]

ok. i tried it with x64 + with x86. it doesn't work.
try my globalInputHook class in my signature...

[tropix100]

.paul.
Again thanks for your reply.
I know it doesnt work. Thats why I came here for help.
I want to know WHY it doesnt work. I have a lot of respect for what I have seen of Paul Kimmel and I believe his code should work.
Why doesnt it? What is causing the error. There are many alternatives I can find but I chose to come here for help with the option I am using.

Your signiture?....I dont see one.
Please feel free to post it here and I will try it.
Thanks .paul.

[.paul.]

if i knew why it doesn't work, i would've told you
it's probably an error in transcription somewhere.


http://www.vbforums.com/showthread.php?t=637302

[tropix100]

mmm....Or promote your own..

Anyway....I had a look at your code and it looks very similar to what I am trying to get to work now. Although yours is much more comprehensive.
I have added it to my project but cant reference it.
What have I missed.
It is late here and I am tired so the simple things are boing missed
Your help is appreciated.

[.paul.]

you just need to add the class to your project. after rebuilding, you'll find it (it's a component), at the top of your toolbox

also if you read the complete thread i gave the link for, you'll see what others have said about their experience with it...

[tropix100]

Im not really concerned about others experience...Its only mine that counts
WOW...ya lost me....
I have no prob adding the file to my project but I cant reference it......If I continue to build it I will replace Londons gerkin.
It does not show up anywhere........and Im not able to reference it.
Grrrr.....


Not your fault Im sure....something sooo simple becomes such a big prob.

[tropix100]

Strangely enough it was in my tools after reloading so its all good.
Its working now but I will need to spend a while to now try to understand some of the code and and what its doing. Vastly different to 6.
Thanks so much .paul. your persevering help has paid of for me.
Greatly appreciated.
Thanks.