//中文转为UNICODE字符

string str = "中文";
            string outStr = "";
            if (!string.IsNullOrEmpty(str))
            {               
                for (int i = 0; i < str.Length; i++)
                {
                    //将中文字符转为10进制整数，然后转为16进制unicode字符
                    outStr += "\\u" + ((int)str[i]).ToString("x");
                }
            }

//UNICODE字符转为中文

            string str = "\\u4e2d\\u6587";
            string outStr = "";
            if (!string.IsNullOrEmpty(str))
            {
                string[] strlist = str.Replace("\\","").Split('u');
                try
                {
                    for (int i = 1; i < strlist.Length; i++)
                    {
                        //将unicode字符转为10进制整数，然后转为char中文字符
                        outStr += (char)int.Parse(strlist[i], System.Globalization.NumberStyles.HexNumber);
                    }
                }
                catch (FormatException ex)
                {
                    outStr = ex.Message;
                }
            }