防止将Chrome标签拖出窗口屏幕

Question

我目前正在开发一个使用与Google Chrome标签相同的标签的程序， 标签工作正常，没问题。 但我遇到的情况是我可以将标签拖出显示器屏幕（左右边缘）。

问题是，如何限制拖动到屏幕边缘的标签？ 因此标签不会通过屏幕。基本上它只是关于审美目的.. 请注意，我已经从谷歌和这个网站进行了研究，但仍然无法弄清楚如何做到这一点。

这是一段代码。

    private bool draggingWindow;
    private Size finalSize;
    private double overlap;
    private double leftMargin;
    private double rightMargin;
    private double maxTabWidth;
    private double minTabWidth;
    private double defaultMeasureHeight;
    private double currentTabWidth;
    private int captureGuard;
    private int originalIndex;
    private int slideIndex;
    private List<double> slideIntervals;
    private ChromeTabItem draggedTab;
    private Point downPoint;
    private ChromeTabControl parent;

    public Rect addButtonRect;
    private Size addButtonSize;
    public Button addButton;

    private bool modifyLeftOffset, modifyTopOffset;
    private Point origCursorLocation;
    private double origHorizOffset, origVertOffset;

    protected override void OnPreviewMouseMove(MouseEventArgs e)
    {
        try
        {
            base.OnPreviewMouseMove(e);
            if (this.addButtonRect.Contains(e.GetPosition(this)) && this.addButton.Background != Brushes.White && this.addButton.Background != Brushes.DarkGray)
            {
                this.addButton.Background = Brushes.White;
                this.InvalidateVisual();
            }
            else if (!this.addButtonRect.Contains(e.GetPosition(this)) && this.addButton.Background != null)
            {
                this.addButton.Background = null;
                this.InvalidateVisual();
            }

            if (this.draggedTab == null || this.draggingWindow) { return; }
            Point nowPoint = e.GetPosition(this);
            this.addButton.Visibility = Visibility.Hidden;
            double newHorizontalOffset;

            if (this.modifyLeftOffset)
                newHorizontalOffset = this.origHorizOffset + (nowPoint.X - this.origCursorLocation.X);
            else
                newHorizontalOffset = this.origHorizOffset - (nowPoint.X - this.origCursorLocation.X);

            Thickness margin = new Thickness(nowPoint.X - this.downPoint.X, 0, this.downPoint.X - nowPoint.X, 0);
            this.draggedTab.Margin = margin;

            Rect elemRect = this.CalculateDragElementRect(newHorizontalOffset, 1);
            bool leftAlign = elemRect.Left < 0;
            bool rightAlign = elemRect.Right > this.ActualWidth;

            if (leftAlign)
                newHorizontalOffset = modifyLeftOffset ? 0 : this.ActualWidth - elemRect.Width;
            else if (rightAlign)
                newHorizontalOffset = modifyLeftOffset ? this.ActualWidth - elemRect.Width : 0;

            if (this.modifyLeftOffset)
                Canvas.SetLeft(this.draggedTab, newHorizontalOffset);
            else
                Canvas.SetRight(this.draggedTab, newHorizontalOffset);

            base.OnPreviewMouseMove( e );

            if (margin.Left != 0)
            {
                int guardValue = Interlocked.Increment(ref this.captureGuard);
                if (guardValue == 1)
                {
                    this.originalIndex = this.draggedTab.Index;
                    this.slideIndex = this.originalIndex + 1;
                    this.slideIntervals = new List<double>();
                    this.slideIntervals.Add(double.NegativeInfinity);
                    for (int i = 1; i <= this.Children.Count; i += 1)
                    {
                        var diff = i - this.slideIndex;
                        var sign = diff == 0 ? 0 : diff / Math.Abs(diff);
                        var bound = Math.Min(1, Math.Abs(diff)) * ((sign * this.currentTabWidth / 3) + ((Math.Abs(diff) < 2) ? 0 : (diff - sign) * (this.currentTabWidth - this.overlap)));
                        this.slideIntervals.Add(bound);
                    }
                    this.slideIntervals.Add(double.PositiveInfinity);
                    this.CaptureMouse();

                }
                else
                {
                    int changed = 0;
                    if (this.slideIntervals != null)
                    {
                        if (margin.Left < this.slideIntervals[this.slideIndex - 1])
                        {
                            SwapSlideInterval(this.slideIndex - 1);
                            this.slideIndex -= 1;
                            changed = 1;
                        }
                        else if (margin.Left > this.slideIntervals[this.slideIndex + 1])
                        {
                            SwapSlideInterval(this.slideIndex + 1);
                            this.slideIndex += 1;
                            changed = -1;
                        }
                    }
                    if (changed != 0)
                    {
                        var rightedOriginalIndex = this.originalIndex + 1;
                        var diff = 1;
                        if (changed > 0 && this.slideIndex >= rightedOriginalIndex)
                        {
                            changed = 0;
                            diff = 0;
                        }
                        else if (changed < 0 && this.slideIndex <= rightedOriginalIndex)
                        {
                            changed = 0;
                            diff = 2;
                        }
                        ChromeTabItem shiftedTab = this.Children[this.slideIndex - diff] as ChromeTabItem;
                        if (shiftedTab != this.draggedTab)
                        {
                            StickyReanimate(shiftedTab, changed * (this.currentTabWidth - this.overlap), .13);
                        }
                    }
                }
            }
        }

        catch (Exception ex)
        {
            throw ex;
        }

    }

真的很感激任何回应和关注。

谢谢