Inserts HTML line breaks (<br />) before all newlines

StringTransformer.AddHtmlLineBreaks

    public static class StringTransformer
    {
        /// <summary>
        /// Inserts HTML line breaks (&lt;br /&gt;) before all newlines.
        /// </summary>
        /// <param name="text">text containing lines</param>
        /// <returns></returns>
        public static string AddHtmlLineBreaks(this string text)
        {
            if (text == null)
                return null;
            if (text.Contains("\r\n"))
                return text.Replace("\r\n", "<br />\r\n");
            else if (text.Contains("\n"))
                return text.Replace("\n", "<br />\n");
            else if (text.Contains("\r"))
                return text.Replace("\r", "<br />\r");
            else
                return text;
        }
    }