C#

<br />
GCHandle handle = GCHandle.Alloc( savedArray, GCHandleType.Pinned );<br />
int scan0 = (int) handle.AddrOfPinnedObject();<br />
scan0 += (h - 1) * stride;<br />
Bitmap b = new Bitmap( w, h, -stride, PixelFormat.Format24bppRgb, (IntPtr) scan0 );<br />
handle.Free();<br />

Protected Overrides Sub WndProc(ByRef msg As Message)
    Select Case msg.Msg
        Case 131 'WM_NCCALCSIZE
            ...
        Case 132 'WM_NCHITTEST
            ...
        Case 133 'WM_NCPAINT
            Dim dc As Integer
            dc = GetDCEx(msg.HWnd.ToInt32(), msg.WParam.ToInt32(), 65536 + 128 + 1)
            Dim hdc As IntPtr = New IntPtr(dc)
            Dim g As Graphics = Graphics.FromHdc(hdc)
            OnPaintNonClient(New PaintEventArgs(g, Rectangle.Round(g.ClipBounds)))
            ReleaseDC(msg.HWnd.ToInt32(), hdc.ToInt32())
        Case 160 'WM_NCMOUSEMOVE
            Dim pt As PointL
            pt.x = msg.LParam.ToInt32() Mod 65536
            pt.y = msg.LParam.ToInt32() / 65536
            Dim ppt As IntPtr = Marshal.AllocHGlobal(8)
            Marshal.StructureToPtr(pt, ppt, False)
            ScreenToClient(msg.HWnd.ToInt32(), ppt.ToInt32())
            pt = Marshal.PtrToStructure(ppt, GetType(PointL))
            Dim args As MouseEventArgs = New MouseEventArgs(MouseButtons.None, 0, pt.x, pt.y, 0)
            OnNonClientMouseMove(args)
            Marshal.FreeHGlobal(ppt)
        Case 161 'WM_NCLBUTTONDOWN
            ...
        Case 162 'WM_NCLBUTTONUP
            ...
        Case Else
            MyBase.WndProc(msg)
    End Select
End Sub

Protected Overridable Sub OnNonClientMouseMove(ByVal args As MouseEventArgs)
    If ... Then 'Test hotspots
        ...
        PostMessage(Me.Handle, 133, 0, 0) 'WM_NCPAINT
    End If
End Sub

Protected Overridable Sub OnPaintNonClient(ByVal args As PaintEventArgs)
    ...
End Sub