How to prevent ALt+F4

[Latin4567]

well i have gotten it to work by forcing the window to always have focus and be ontop... so it goes ontop of the taskmanager rendering it useless... and i already disabled ALT+F4....
yay!

[TTn]

Imports System.Drawing
Imports System.Threading
Imports System.Reflection
Imports System.Runtime.InteropServices
Friend Class Form1
    Inherits System.Windows.Forms.Form
#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'Form overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.IContainer

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer. 
    'Do not modify it using the code editor.
    Friend WithEvents Button1 As System.Windows.Forms.Button
    Friend WithEvents Button2 As System.Windows.Forms.Button

    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.Button1 = New System.Windows.Forms.Button
        Me.Button2 = New System.Windows.Forms.Button
        Me.SuspendLayout()
        '
        'Button1
        '
        Me.Button1.Location = New System.Drawing.Point(88, 72)
        Me.Button1.Name = "Button1"
        Me.Button1.Size = New System.Drawing.Size(128, 24)
        Me.Button1.TabIndex = 1
        Me.Button1.Text = "Disable task manager."
        '
        'Button2
        '
        Me.Button2.Location = New System.Drawing.Point(88, 112)
        Me.Button2.Name = "Button2"
        Me.Button2.Size = New System.Drawing.Size(128, 24)
        Me.Button2.TabIndex = 2
        Me.Button2.Text = "Enable Task manager"
        '
        'Form1
        '
        Me.AutoScaleBaseSize = New System.Drawing.Size(5, 13)
        Me.ClientSize = New System.Drawing.Size(292, 266)
        Me.Controls.Add(Me.Button2)
        Me.Controls.Add(Me.Button1)
        Me.Name = "Form1"
        Me.Text = "                 Ctrl + Alt + Delete"
        Me.ResumeLayout(False)

    End Sub

#End Region

    Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vKey As Integer) As Integer
    Public Declare Function UnhookWindowsHookEx Lib "user32" (ByVal hHook As Integer) As Integer
    Private Declare Sub keybd_event Lib "user32.dll" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Integer, ByVal dwExtraInfo 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 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

    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

    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 KeyboardHandle As Integer

    ' Low-Level Keyboard Constant
    Const HC_ACTION As Integer = 0

    ' Virtual Keys
    Const KEYEVENTF_KEYUP As Short = &H2
    Const VK_SHIFT As Integer = &H10
    Const VK_CONTROL = &H11
    Const VK_DELETE = &H2E
    Const VK_MENU = &H12
    Const VK_ESCAPE As Integer = &H1B
    Const WH_KEYBOARD_LL As Integer = 13&


    'This function allows keys to be detected and dealt with.
    Public Function IsHooked(ByRef Hookstruct As KBDLLHOOKSTRUCT) As Boolean
        On Error Resume Next

        ' ctrl alt delete, can be detected here. The task manager is closed.
        If (Hookstruct.vkCode = VK_DELETE) And CBool(GetAsyncKeyState(VK_MENU) And &H8000) And CBool(GetAsyncKeyState(VK_CONTROL) And &H8000) Then
            Do
                Application.DoEvents()
                SendKeys.Flush()
                Dim clt() As Process = Process.GetProcessesByName("taskmgr")
                For Each p As Process In clt

                    'kill task manager and rip from memory
                    p.Kill()

                    'Thanks to Dan Appleman, who doesn't know why either.
                    Application.DoEvents()
                    SendKeys.Flush()

                    'Return Task Manager function here, to replace memory.
                    'Simulate Ctrl Shift Esc to call task managers back to duty.
                    keybd_event(VK_CONTROL, 0, 0, 0)
                    keybd_event(VK_SHIFT, 0, 0, 0)
                    keybd_event(VK_ESCAPE, 0, 0, 0)
                    keybd_event(VK_ESCAPE, 0, KEYEVENTF_KEYUP, 0)
                    keybd_event(VK_SHIFT, 0, KEYEVENTF_KEYUP, 0)
                    keybd_event(VK_CONTROL, 0, KEYEVENTF_KEYUP, 0)
                    'END--Ctrl Alt Delete has been essentially blocked here from bringing up the task manager.
                    'If you want to personalize your own application's task manager.
                    'Call MyTaskMangerReplacement(1) 
                    Application.DoEvents()
                    SendKeys.Flush()
                    Exit Do
                Next
                Application.DoEvents()
                SendKeys.Flush()
            Loop
        End If

        'disable task manager for, control shift esc.
        If (Hookstruct.vkCode = VK_ESCAPE) And CBool(GetAsyncKeyState(VK_CONTROL) And &H8000) And CBool(GetAsyncKeyState(VK_SHIFT) And &H8000) Then
            Return True
        End If

        Return False
    End Function

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

    ' UnhookKeyboard is very important to include in the form's unload.
    Public Sub UnhookKeyboard()
        If (Hooked()) Then
            Call UnhookWindowsHookEx(KeyboardHandle)
        End If
    End Sub

    'Indicates hook success.
    Private Function Hooked()
        Hooked = KeyboardHandle <> 0
    End Function

    Public Function KeyboardCallback(ByVal Code As Integer, ByVal wParam As Integer, ByRef lParam As KBDLLHOOKSTRUCT) As Integer
        If (Code = HC_ACTION) Then
            If (IsHooked(lParam)) Then
                Return 1
            End If
        End If
        Return CallNextHookEx(KeyboardHandle, Code, wParam, lParam)
    End Function

    Private Sub Form1_Closed(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Closed
        On Error Resume Next

        'unhook keyboard control
        UnhookKeyboard()
    End Sub

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

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        On Error Resume Next
        UnhookKeyboard()
    End Sub
End Class