Ayuda con este error "CallbackOnCollectedDelegate was detected"

Question

Hola a Todos estoy tratando de que mi apicacion en vb 2010 frame work 4 desabilite las teclas  de windows, ctrl y esc, alt ytab

consegui el codigo que les muestro en lared, y me marca el siguiente error:

 "CallbackOnCollectedDelegate was detected
Message: A callback was made on a garbage collected delegate of type 'RMS Tech!RMS_Tech.BloqueTeclas+LowLevelKeyboardProcDelegate::Invoke'.
This may cause application crashes, corruption and data loss. When passing delegates to unmanaged code,
they must be kept alive by the managed application until it is guaranteed that they will never be called."

les  agradesco su ayuda gracias

Public NotInheritable Class BloqueTeclas

    Declare Function SetWindowsHookEx Lib "user32" Alias "SetWindowsHookExA" (ByVal idHook As Integer, ByVal lpfn As LowLevelKeyboardProcDelegate, ByVal hMod As IntPtr, ByVal dwThreadId As Integer) As IntPtr
    Declare Function UnhookWindowsHookEx Lib "user32" Alias "UnhookWindowsHookEx" (ByVal hHook As IntPtr) As Boolean
    Declare Function CallNextHookEx Lib "user32" Alias "CallNextHookEx" (ByVal hHook As IntPtr, ByVal nCode As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer
    Public Delegate Function LowLevelKeyboardProcDelegate(ByVal nCode As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer
    Const WH_KEYBOARD_LL As Integer = 13

    Structure KBDLLHOOKSTRUCT
        Dim vkCode As Integer
        Dim scanCode As Integer
        Dim flags As Integer
        Dim time As Integer
        Dim dwExtraInfo As Integer
    End Structure
    Shared intLLKey As IntPtr
    Private Shared Function LowLevelKeyboardProc(ByVal nCode As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer
        Dim blnEat As Boolean = False
        Select Case wParam
            Case 256, 257, 260, 261
                'Alt+Tab, Alt+Esc, Ctrl+Esc, Windows Key    
                blnEat = ((lParam.vkCode = 9) AndAlso (lParam.flags = 32)) Or _
                ((lParam.vkCode = 27) AndAlso (lParam.flags = 32)) Or _
                ((lParam.vkCode = 27) AndAlso (lParam.flags = 0)) Or _
                ((lParam.vkCode = 91) AndAlso (lParam.flags = 1)) Or _
                ((lParam.vkCode = 92) AndAlso (lParam.flags = 1))
        End Select
        If blnEat = True Then
            Return 1
        Else
            Return CallNextHookEx(IntPtr.Zero, nCode, wParam, lParam)
        End If

    End Function

    Public Shared Sub Show()
        BloqueTeclas.SetVisibility(True)
    End Sub

    Public Shared Sub Hide()
        BloqueTeclas.SetVisibility(False)
    End Sub
    Private Shared Sub SetVisibility(ByVal show As Boolean)
        Dim intLLKey1 As New IntPtr

        If show = False Then
            intLLKey = SetWindowsHookEx(WH_KEYBOARD_LL, AddressOf LowLevelKeyboardProc, IntPtr.Zero, 0)
        End If
        If show = True Then
            UnhookWindowsHookEx(intLLKey)
        End If
    End Sub
End Class

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Alvaro

Answer 1

  intLLKey = SetWindowsHookEx(WH_KEYBOARD_LL, New  LowLevelKeyboardProcDelegate( LowLevelKeyboardProc), IntPtr.Zero, 0)

debes instanciar un dlegado LowLevelKeyboardProcDelegate...

espero funcione
       

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Si se solucionó tu consulta no olvides marcar la respuesta. Si te ayudó vótala como útil. Saludos

Answer 2

Gracias sergio por responder

me pone el sigiente error:

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Alvaro

Answer 3

Perdona...haz esto por favor

Private KeyboardHookProcedure As Win32.HookProc

KeyboardHookProcedure = New Win32.HookProc(AddressOf LowLevelKeyboardProc)

intLLKey = SetWindowsHookEx(WH_KEYBOARD_LL, KeyboardHookProcedure, Marshal.GetHINSTANCE(Reflection.Assembly.GetExecutingAssembly().GetModules()(0)), 0)

O revisa http://www.colinneller.com/blog/PermaLink,guid,2838f59a-f4af-4c95-a322-b9ee5918a39c.aspx

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Si se solucionó tu consulta no olvides marcar la respuesta. Si te ayudó vótala como útil. Saludos

Answer 4

Gracias Sergio  cheque la liga que me  Pasaste y baja el ejemplo

gracias

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Alvaro