Question

I have a RichTextBox displaying a FlowDocument that is large (>10k lines). I am attempting to apply text formatting to the entire Document. This is taking a while to complete.

Is there any way to focus the formatting on the visible parts of the Document only?

For Information: I am attempting to search through the contents of the RichTextBox and highlight all matching occurrences. The searching function is baised upon this one. I am using the following code to ‘highlight’ each match found.

protected void ColorTextRanges(Color color)
{
    foreach ( var textRange in locatedInstances )
    {
        if ( textRange != null )
        {
            textRange.ApplyPropertyValue( TextElement.BackgroundProperty, new SolidColorBrush( color ) );
        }
    }
}

Answer 1

The best performance increase I found was to update the document when out wasn’t displayed on the screen. Not sure sure why this is but I can guess that some thing in the screen buffer isn’t being updated.