正则表达式高效提取数据技术解析

 private DataTable extract(string sourcecode,string startCity,string endCity)
        {
            DataTable da = createCollDataTable();
            string flightcode = "[\u4e00-\u9fff]+含.+?</td>";//航班号
            Regex flightregex = new Regex(flightcode);
            MatchCollection flight = flightregex.Matches(sourcecode);
            string Seatcode = "<span >\r\n.+[A-Z0-9]/";//舱位
            Regex seatco = new Regex(Seatcode);
            MatchCollection seat = seatco.Matches(sourcecode);
            string seatcode1 = "[A-Z0-9]+/";
            Regex seatreg = new Regex(seatcode1);
            string rebate = @"[0-9]+\.[0-9]{1}\r";//折扣率
            Regex reba=new Regex(rebate);
            MatchCollection rebatecode = reba.Matches(sourcecode);
            string effectivedata="<td align=\"center\" style=\"width:50px;\">\r\n\\s+[0-9]{2}-[0-9]{2}-[0-9]{2}<br />\r\n\\s+[0-9]{2}-[0-9]{2}-[0-9]{2}";//有效日期，出票日期
            Regex effectiveda = new Regex(effectivedata);
            MatchCollection effective = effectiveda.Matches(sourcecode);
            string data = "[0-9]{2}-[0-9]{2}-[0-9]{2}";
            Regex efdata = new Regex(data);
            string iss = "id=\"gvList_ctl[0-9]{2}_btnCan\"";
            Regex issef = new Regex(iss);
            MatchCollection isse = issef.Matches(sourcecode);
            Regex clude = new Regex("[\u4e00-\u9fff]+含：");
            Regex include = new Regex("[0-9A-Z]{6}");
            int count=seat.Count;
            for (int i = 0; i < count; i++)
            {
                tol++;
                MatchCollection flight1 = include.Matches(flight[i].Value);
                MatchCollection seat1 = seatreg.Matches(seat[i].Value);