.net 正则封装类

 /// <summary>
        /// 获取一个
        /// </summary>
        /// <param name="源字符串"></param>
        /// <param name="正则表达式"></param>
        /// <param name="开始字符串"></param>
        /// <returns></returns>
        public static string 正则获取(string 源字符串, string 正则表达式)
        {
            try
            {
                JArray li = 正则获取(源字符串, 正则表达式, "");
                return li.Count > 0 ? li[0].ToString() : "";
            }
            catch (Exception)
            {


            }
            return "";
        }
        /// <summary>
        /// 获取括号里的内容(.*?)
        /// </summary>
        /// <param name="源字符串"></param>
        /// <param name="正则表达式"></param>
        /// <param name="开始字符串"></param>
        /// <returns></returns>
        public static JArray 正则获取(string 源字符串, string 正则表达式, string 开始字符串)
        {