Hello,

I have been looking into your requirement and created a small sample with XamRichTextEditor and two buttons Up/Down.

In order to get the vertical scrollbar and be able to modify it on button click or any other event you could use the following code:

var scrollBar = Utilities.GetDescendantFromType((this.xrte1), typeof(ScrollBar), true) as ScrollBar;

After that you could change the scroll bar value using its Value property:

void scrolling (ScrollBar scrollBar, string direction)
{
     if(direction == "up")
     {
         while (true)
         {
             this.Dispatcher.Invoke((Action)(() =>
            {
                scrollBar.Value -= scrollBar.SmallChange;
             }));
           Thread.Sleep(300);
          }
     }
   else
   {
        while (true)
       {
            this.Dispatcher.Invoke((Action)(() =>
            {
               scrollBar.Value += scrollBar.SmallChange;
            }));
           Thread.Sleep(300);
        }
   }
}

In order to keep scrolling till the mouse is up, I'm using a thread that would start and call the scrolling method until it is aborted in the button PreviewMouseUp event handler.

I have attached my sample below. Please test it on your side and let me know if I may be of any further assistance.

Sincerely,

Teodosia Hristodorova

Associate Software Developer

5415.XamRichTextEditor_scroll_buttons.zip

4505.XamRichTextEditor_scroll_buttons.zip