Highlight search text functions using css tags and regex

    protected string HighlightText(string searchWord, string inputText)
    {

        Regex expression = new Regex(searchWord.Replace(" ", "|")); 
        // Regex.ignorecase

        return expression.Replace(inputText, new MatchEvaluator(ReplaceKeywords)); 
    }
     public string ReplaceKeywords(Match m)
    {
        return "<span class='highlight'>" + m.Value + "</span>"; 
    }