public static void HighLight(RichTextBox chatRichTextBox, int left, int right, TextStyleSaver saver)
{
saver.CopyFrom(chatRichTextBox, left, right);
chatRichTextBox.SelectionFont = new Font(chatRichTextBox.SelectionFont ?? chatRichTextBox.Font, /*FontStyle.Bold | */ FontStyle.Underline);
chatRichTextBox.SelectionLength = 0;
}