//返回首页
 private void ClickedToBack3(Object sender, RoutedEventArgs e)
 {
     if (RightWebView.CanGoBack)
     {
         RightWebView.GoBack();
     }
 }
        //双屏
        void ClickedTwoScreen(Object sender, RoutedEventArgs e)
        {
            Now_Page.Visibility    = Visibility.Collapsed;
            Double_Page.Visibility = Visibility.Visible;


            Uri Left_uri = new Uri(leftUri);

            LeftWebView.Navigate(Left_uri);

            if (!bRightWebviewIsOpen)
            {
                Uri Right_uri = new Uri(leftUri);
                RightWebView.Navigate(Right_uri);
            }
            else
            {
                Uri Right_uri = new Uri(rightUri);
                RightWebView.Navigate(Right_uri);
            }
        }
        //双屏同步
        private void ClickedTwoScreen3(Object sender, RoutedEventArgs e)
        {
            Uri Right_uri = new Uri(nowUri);

            RightWebView.Navigate(Right_uri);
        }