ZForge.Controls.TreeViewAdv.Tree.TreeViewAdv.DragAutoScroll C# (CSharp) Method

        private void DragAutoScroll()
        {
            _dragAutoScrollFlag = false;
            Point pt = PointToClient(MousePosition);
            if (pt.Y < 20 && _vScrollBar.Value > 0)
                _vScrollBar.Value--;
            else if (pt.Y > Height - 20 && _vScrollBar.Value <= _vScrollBar.Maximum - _vScrollBar.LargeChange)
                _vScrollBar.Value++;
        }