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Option Explicit

Private Const GWL_STYLE = (-16)

Private Const WS_SYSMENU = &H80000

Private Const WS_CAPTION = &HC00000

Private Const WS_THICKFRAME = &H40000

Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long) As Long

Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" (ByVal hwnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long





Private Const WS_BORDER = &H800000

Public Sub EnableResizing(Form As Form, Enable As Boolean)

    Dim style As Long



    style = GetWindowLong(Form.hwnd, GWL_STYLE)

    If Enable Then

        style = style Or WS_THICKFRAME

    Else

        style = style And Not WS_THICKFRAME

    End If

    style = SetWindowLong(Form.hwnd, GWL_STYLE, style)

End Sub





Private Sub MDIForm_Load()

    Show

    EnableResizing Me, False

Dim lStyle As Long

  lStyle = GetWindowLong(MDIForm1.hwnd, GWL_STYLE) 'Get's the WindowLong



  lStyle = lStyle And Not WS_BORDER

 ' lStyle = lStyle And Not WS_BORDER

 ' lStyle = lStyle And Not WS_CAPTION

 ' lStyle = lStyle And WS_BORDER And Not WS_CAPTION

  

Call SetWindowLong(MDIForm1.hwnd, GWL_STYLE, lStyle)

End Sub