AvalonEdit WPF TextEditor (SharpDevelop): How to highlight a specific range of text?

Question

The incredibly awesome AvalonEdit WPF TextEditor control seems to lack an important feature, or at least i can\'t figure it out. Given an offset and a length, highli

Answer 1

Did you see this in this article - it seems to be exactly what are you asking for:

public class ColorizeAvalonEdit : DocumentColorizingTransformer
{
protected override void ColorizeLine(DocumentLine line)
{
    int lineStartOffset = line.Offset;
    string text = CurrentContext.Document.GetText(line);
    int start = 0;
    int index;
    while ((index = text.IndexOf("AvalonEdit", start)) >= 0) {
        base.ChangeLinePart(
            lineStartOffset + index, // startOffset
            lineStartOffset + index + 10, // endOffset
            (VisualLineElement element) => {
                // This lambda gets called once for every VisualLineElement
                // between the specified offsets.
                Typeface tf = element.TextRunProperties.Typeface;
                // Replace the typeface with a modified version of
                // the same typeface
                element.TextRunProperties.SetTypeface(new Typeface(
                    tf.FontFamily,
                    FontStyles.Italic,
                    FontWeights.Bold,
                    tf.Stretch
                ));
            });
        start = index + 1; // search for next occurrence
}   }   }

It highlights word AvalonEdit with bold.