Override Form Maximize and Restore?

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VB

VB10

Hi, I am trying to override the message that is sent by the forms maximize button and I would like to create my own version of the form maximized state.

My application requires to be in a specific aspect ratio while resizing and I want to allow the user to maximize the form, but only to the given aspect ratio. This will work if I set form maximum size. But I also want it to be positioned in the centre of the screen, so that it is more professional. I have all the calculations for it's sizing I just need to be able to make that sizing happen :p

Here is some code I got from some other forums (converted from C# to VB.Net), but I am not sure how to use it - as I'm quite new to this override business :p:

Imports System.Runtime.InteropServices

<DllImport("user32.dll")> _
Private Shared Function SetWindowLongPtr(hWnd As IntPtr, nIndex As Integer, dwNewLong As Integer) As Integer
End Function

<DllImport("user32.dll", SetLastError:=True)> _
Private Shared Function GetWindowLongPtr(hWnd As IntPtr, nIndex As Integer) As Integer
End Function

<DllImport("user32.dll")> _
Private Shared Function SetWindowPos(hWnd As IntPtr, hWndInsertAfter As IntPtr, X As Integer, Y As Integer, cx As Integer, cy As Integer, _
 uFlags As UInteger) As Boolean
End Function

Protected Overrides Sub WndProc(ByRef m As Message)

    Const WS_MAXIMIZE As Integer = &H1000000
    Const GWL_STYLE As Integer = -16
    Const WM_SYSCOMMAND As Integer = &H112
    Const SC_MAXIMIZE As Integer = &HF030
    Const SC_RESTORE As Integer = &HF120
    Static HWND_TOP As IntPtr = 0
    Const SWP_SHOWWINDOW As Integer = &H40
    Const SWP_NOZORDER As Integer = &H4
    Const SWP_NOMOVE As Integer = &H2
    Const SWP_DRAWFRAME As Integer = &H20

    If m.Msg = WM_SYSCOMMAND Then
        If CInt(m.WParam) = SC_MAXIMIZE Then
            MessageBox.Show("Maximized!!")
            Dim iStyle As Integer = GetWindowLong(Me.Handle, GWL_STYLE)
            SetWindowLong(Me.Handle, GWL_STYLE, iStyle Or WS_MAXIMIZE)
            SetWindowPos(Me.Handle, HWND_TOP, 0, 0, Me.Width, Me.Height, _
                         SWP_DRAWFRAME Or SWP_NOMOVE Or SWP_NOZORDER Or _
                         SWP_SHOWWINDOW)
            Return
        End If

        If CInt(m.WParam) = SC_RESTORE Then
            MessageBox.Show("Restored down!!")
            Dim iStyle As Integer = GetWindowLong(Me.Handle, GWL_STYLE)
            SetWindowLong(Me.Handle, GWL_STYLE, iStyle And Not WS_MAXIMIZE)
            SetWindowPos(Me.Handle, HWND_TOP, 0, 0, Me.Width, Me.Height, _
                         SWP_DRAWFRAME Or SWP_NOMOVE Or SWP_NOZORDER Or _
                         SWP_SHOWWINDOW)
            Return
        End If
    End If

    MyBase.WndProc(m)

End Sub

This code simply sets the forms window state to maximized without changing it's size or location. I simply want it to maximize to the screen's working area while maintaining a given aspect ratio and being centred.

Thanks in advance!