C# 将\u1234类型的字符转化成汉字

 /// <summary>
        /// 
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static string DeCode(string str)
        {
            var regex = new Regex(@"\\u(\w{4})");

            string result = regex.Replace(str, delegate(Match m)
            {
                string hexStr = m.Groups[1].Value;
                string charStr = ((char)int.Parse(hexStr, System.Globalization.NumberStyles.HexNumber)).ToString();
                return charStr;
            });

            return result;
        }