[StructLayout(LayoutKind.Sequential)]
        struct RECT
        {
            public int left;
            public int top;
            public int right;
            public int bottom;
        }

        [StructLayout(LayoutKind.Sequential)]
        struct APPBARDATA
        {
            public int cbSize;
            public IntPtr hWnd;
            public int uCallbackMessage;
            public int uEdge;
            public RECT rc;
            public IntPtr lParam;
        }

        enum ABMsg : int
        {
            ABM_NEW = 0,
            ABM_REMOVE = 1,
            ABM_QUERYPOS = 2,
            ABM_SETPOS = 3,
            ABM_GETSTATE = 4,
            ABM_GETTASKBARPOS = 5,
            ABM_ACTIVATE = 6,
            ABM_GETAUTOHIDEBAR = 7,
            ABM_SETAUTOHIDEBAR = 8,
            ABM_WINDOWPOSCHANGED = 9,
            ABM_SETSTATE = 10
        }

        enum ABNotify : int
        {
            ABN_STATECHANGE = 0,
            ABN_POSCHANGED,
            ABN_FULLSCREENAPP,
            ABN_WINDOWARRANGE
        }

        enum ABEdge : int
        {
            ABE_LEFT = 0,
            ABE_TOP,
            ABE_RIGHT,
            ABE_BOTTOM
        }

        private bool fBarRegistered = false;

        [DllImport("SHELL32", CallingConvention = CallingConvention.StdCall)]
        static extern uint SHAppBarMessage(int dwMessage, ref APPBARDATA pData);
        [DllImport("USER32")]
        static extern int GetSystemMetrics(int Index);
        [DllImport("User32.dll", ExactSpelling = true,
            CharSet = System.Runtime.InteropServices.CharSet.Auto)]
        private static extern bool MoveWindow
            (IntPtr hWnd, int x, int y, int cx, int cy, bool repaint);
        [DllImport("User32.dll", CharSet = CharSet.Auto)]
        private static extern int RegisterWindowMessage(string msg);
        private int uCallBack;

        private void RegisterBar()
        {
            APPBARDATA abd = new APPBARDATA();
            abd.cbSize = Marshal.SizeOf(abd);
            abd.hWnd = this.Handle;
            if (!fBarRegistered)
            {
                uCallBack = RegisterWindowMessage("AppBarMessage");
                abd.uCallbackMessage = uCallBack;

                uint ret = SHAppBarMessage((int)ABMsg.ABM_NEW, ref abd);
                fBarRegistered = true;

                ABSetPos();
            }
            else
            {
                SHAppBarMessage((int)ABMsg.ABM_REMOVE, ref abd);
                fBarRegistered = false;
            }
        }

        private void ABSetPos()
        {
            APPBARDATA abd = new APPBARDATA();
            abd.cbSize = Marshal.SizeOf(abd);
            abd.hWnd = this.Handle;
            abd.uEdge = (int)ABEdge.ABE_TOP;

            if (abd.uEdge == (int)ABEdge.ABE_LEFT || abd.uEdge == (int)ABEdge.ABE_RIGHT)
            {
                abd.rc.top = 0;
                abd.rc.bottom = SystemInformation.PrimaryMonitorSize.Height;
                if (abd.uEdge == (int)ABEdge.ABE_LEFT)
                {
                    abd.rc.left = 0;
                    abd.rc.right = Size.Width;
                }
                else
                {
                    abd.rc.right = SystemInformation.PrimaryMonitorSize.Width;
                    abd.rc.left = abd.rc.right - Size.Width;
                }

            }
            else
            {
                abd.rc.left = 0;
                abd.rc.right = SystemInformation.PrimaryMonitorSize.Width;
                if (abd.uEdge == (int)ABEdge.ABE_TOP)
                {
                    abd.rc.top = 0;
                    abd.rc.bottom = Size.Height;
                }
                else
                {
                    abd.rc.bottom = SystemInformation.PrimaryMonitorSize.Height;
                    abd.rc.top = abd.rc.bottom - Size.Height;
                }
            }

            // Query the system for an approved size and position. 
            SHAppBarMessage((int)ABMsg.ABM_QUERYPOS, ref abd);

            // Adjust the rectangle, depending on the edge to which the 
            // appbar is anchored. 
            switch (abd.uEdge)
            {
                case (int)ABEdge.ABE_LEFT:
                    abd.rc.right = abd.rc.left + Size.Width;
                    break;
                case (int)ABEdge.ABE_RIGHT:
                    abd.rc.left = abd.rc.right - Size.Width;
                    break;
                case (int)ABEdge.ABE_TOP:
                    abd.rc.bottom = abd.rc.top + Size.Height;
                    break;
                case (int)ABEdge.ABE_BOTTOM:
                    abd.rc.top = abd.rc.bottom - Size.Height;
                    break;
            }

            // Pass the final bounding rectangle to the system. 
            SHAppBarMessage((int)ABMsg.ABM_SETPOS, ref abd);

            // Move and size the appbar so that it conforms to the 
            // bounding rectangle passed to the system. 
            MoveWindow(abd.hWnd, abd.rc.left, abd.rc.top,
                abd.rc.right - abd.rc.left, abd.rc.bottom - abd.rc.top, true);
        }

        protected override void WndProc(ref System.Windows.Forms.Message m)
        {
            if (m.Msg == uCallBack)
            {
                switch (m.WParam.ToInt32())
                {
                    case (int)ABNotify.ABN_POSCHANGED:
                        ABSetPos();
                        break;
                }
            }

            base.WndProc(ref m);
        }

        protected override System.Windows.Forms.CreateParams CreateParams
        {
            get
            {
                CreateParams cp = base.CreateParams;
                cp.Style &= (~0x00C00000); // WS_CAPTION
                cp.Style &= (~0x00800000); // WS_BORDER
                cp.ExStyle = 0x00000080 | 0x00000008; // WS_EX_TOOLWINDOW | WS_EX_TOPMOST
                return cp;
            }
        }