public string GetObjectXml(string sql, string conn, string className)
        {
            var objXml = new StringBuilder();
            objXml.Append("<?xml version=\"1.0\" encoding=\"utf-16\"?>").Append(Environment.NewLine);
            objXml.Append(string.Format("<{0} xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xmlns:xsd=\"http://www.w3.org/2001/XMLSchema\">", className)).Append(Environment.NewLine);
            DataSet ds = DbOperater.SelectDataSet(sql, conn);
            DataTable dt = ds.Tables[0];
            for (int i = 0; i < dt.Columns.Count; i++)
            {
                for (int j = 0; j < dt.Rows.Count; j++)
                {
                    string val = dt.Rows[j][i].ToString();
                    var reg = new Regex(@"(?<Year>(?:\d{4}))[-|/](?<Month>\d{1,2})[-|/](?<Day>\d{1,2}) (?<Hour>\d{1,2}):(?<Min>\d{1,2}):(?<Sed>\d{1,2})");
                    if (reg.IsMatch(val))
                    {
                        DateTime date = DateTime.Parse(val);
                        val = date.ToUniversalTime().ToString("s");
                    }
                    objXml.Append(string.Format("<{0}>{1}</{0}>", dt.Columns[i].ColumnName, val)).Append(Environment.NewLine); ;
                }
            }
            objXml.Append(string.Format("</{0}>", className));
            return objXml.ToString();
        }