text: public short GetFontAtIndex(int index){int size = _string.FormatRunCount;UnicodeString.FormatRun currentRun = null;for (int i = 0; i < size; i++){UnicodeString.FormatRun r = _string.GetFormatRun(i);if (r.CharacterPos > index)break;else currentRun = r;}if (currentRun == null)return NO_FONT;else return currentRun.FontIndex;}