Disable Close Button and Prevent Form Being Moved

[jmcilhinney]

What about This

The drawback with that is that you must inherit your form from that class. My class can be added to any form you like, which makes it a little simpler to use. I'd guess that that author has used the same method of disabling the Move menu item though.

[rabid lemming]

Hey,

I thought I would post this and see if it helps...a simple way to disable the close button in vb 2005

Private Const SC_CLOSE As Integer = &HF060
    Private Const MF_ENABLED As Integer = &H0
    Private Const MF_GRAYED As Integer = &H1
    Private Const MF_DISABLED As Integer = &H2
    Declare Function GetSystemMenu Lib "user32" (ByVal hWnd As IntPtr, ByVal revert As Boolean) As IntPtr
    Declare Function EnableMenuItem Lib "user32" (ByVal hMenu As IntPtr, ByVal item As Integer, ByVal enab As Integer) As Boolean
 
    Public Sub EnableExit(ByVal ok As Boolean)
        Try
            Dim hdl As IntPtr = GetSystemMenu(Me.Handle, False)
            Dim arg As Integer = MF_ENABLED
            If Not ok Then arg = MF_DISABLED + MF_GRAYED
            EnableMenuItem(hdl, SC_CLOSE, arg)
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
   End Sub
 
'call  EnableExit(False) in your form load event to disable the clode button

Just thought it might be worth posting this

[jmcilhinney]

Hey,

I thought I would post this and see if it helps...a simple way to disable the close button in vb 2005

Private Const SC_CLOSE As Integer = &HF060
    Private Const MF_ENABLED As Integer = &H0
    Private Const MF_GRAYED As Integer = &H1
    Private Const MF_DISABLED As Integer = &H2
    Declare Function GetSystemMenu Lib "user32" (ByVal hWnd As IntPtr, ByVal revert As Boolean) As IntPtr
    Declare Function EnableMenuItem Lib "user32" (ByVal hMenu As IntPtr, ByVal item As Integer, ByVal enab As Integer) As Boolean
 
    Public Sub EnableExit(ByVal ok As Boolean)
        Try
            Dim hdl As IntPtr = GetSystemMenu(Me.Handle, False)
            Dim arg As Integer = MF_ENABLED
            If Not ok Then arg = MF_DISABLED + MF_GRAYED
            EnableMenuItem(hdl, SC_CLOSE, arg)
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
   End Sub
 
'call  EnableExit(False) in your form load event to disable the clode button

Just thought it might be worth posting this

Have you read my code? That's exactly how it works, but I wrapped it in a class that you can reuse instead of having to add that code to every form.

[TTn]

I had run into that problem before where the button becomes reenabled after resizing the form. I no longer have that problem.

I think I fixed it by declaring the API PROPERLY!
Yes it's wrong that way, and many API will fail sometimes without an Alias.
For example the proper way:

Declare Function apiEnableMenuItem Lib "user32" Alias "EnableMenuItem" (ByVal hMenu As IntPtr, ByVal item As Int32, ByVal enab As Int32) As Boolean

Where the alias name should be different than the function name.
I'll see if I can indeed verify that as the reason, unless the IntPtr may also cause a problem.

[TTn]

I wasn't able to reproduce the quirk, but my comment still stands for API declares.

[rabid lemming]

Opps sorry jmcilhinney my bad

[RobDog888]

I had run into that problem before where the button becomes reenabled after resizing the form. I no longer have that problem.

I think I fixed it by declaring the API PROPERLY!
Yes it's wrong that way, and many API will fail sometimes without an Alias.
For example the proper way:

Declare Function apiEnableMenuItem Lib "user32" Alias "EnableMenuItem" (ByVal hMenu As IntPtr, ByVal item As Int32, ByVal enab As Int32) As Boolean

Where the alias name should be different than the function name.
I'll see if I can indeed verify that as the reason, unless the IntPtr may also cause a problem.

No, that incorrect as in .NET its most proper to use the dllimport attribute as alias' are not used or allowed as EntryPoint is used.

<System.Runtime.InteropServices.DllImport("User32.dll", CharSet:=Runtime.InteropServices.CharSet.Auto, EntryPoint:="EnableMenuItem")> _
Private Shared Function EnableMenuItem(ByVal hMenu As IntPtr, ByVal item As Int32, ByVal enab As Int32) As Boolean
End Function