?? 可得會在以后的實體類中能用到
??? using?System;
using?System.Collections;
using?System.Configuration;
using?System.Data;
using?System.Linq;
using?System.Web;
using?System.Web.Security;
using?System.Web.UI;
using?System.Web.UI.HtmlControls;
using?System.Web.UI.WebControls;
using?System.Web.UI.WebControls.WebParts;
using?System.Xml.Linq;
using?System.Collections.Generic;

namespace?test2
{
????class?Student
????{
????????public?string?First?{?get;?set;?}
????????public?string?Last?{?get;?set;?}
????????public?int?ID?{?get;?set;?}
????????public?string?Street?{?get;?set;?}
????????public?string?City?{?get;?set;?}
????????public?List<int>?Scores;??

????}

????class?Teacher
????{
????????public?string?First?{?get;?set;?}
????????public?string?Last?{?get;?set;?}
????????public?int?ID?{?get;?set;?}
????????public?string?City?{?get;?set;?}
??????
????}

????public?partial?class?_Default?:?System.Web.UI.Page
????{




????????protected?void?Page_Load(object?sender,?EventArgs?e)
????????{
????????????List<Student>?students?=?new?List<Student>()
????????{
????????????new?Student?{First="張",
????????????????Last="三",?
????????????????ID=111,?
????????????????Street="123?Main?Street",
????????????????City="太原",
????????????????Scores=?new?List<int>?{97,?92,?81,?60}},
????????????new?Student?{First="李",
????????????????Last="四",?
????????????????ID=112,
????????????????Street="124?Main?Street",
????????????????City="太原",
????????????????Scores=?new?List<int>?{75,?84,?91,?39}},
????????????new?Student?{First="王",
????????????????Last="五",
????????????????ID=113,
????????????????Street="125?Main?Street",
????????????????City="上海",
????????????????Scores=?new?List<int>?{88,?94,?65,?91}},
????????};

???List<Teacher>?teachers?=?new?List<Teacher>()
????????{????????????????
????????????new?Teacher?{First="李",?Last="老師",?ID=945,?City?=?"太原"},
????????????new?Teacher?{First="趙",?Last="老師",?ID=956,?City?=?"鄭州"},
????????????new?Teacher?{First="秦",?Last="老師",?ID=972,?City?=?"北京"}
????????};

????????????//?相當于sql union 關聯
????????????var?peopleInSeattle?=?(from?student?in?students
???????????????????????????????????where?student.City?==?"太原"
???????????????????????????????????select?student.First+student.Last)
?????????????????????????????????
???????????????????????????.Concat(from?teacher?in?teachers
????????????????????????????????where?teacher.City?==?"太原"
????????????????????????????????select?teacher.First+teacher.Last);



????????????this.Response.Write("老師和學生都生活在太原的是:<br?/>");
????????????//?Execute?the?query.
????????????foreach?(var?person?in?peopleInSeattle)
????????????{
????????????????this.Response.Write(person?+?"<br?/>");
??????????????
????????????}
????????????? //相當于sql inner
????????????var?query?=?students.AsQueryable().Join(teachers,
????????????????????????student?=>?student.City,
????????????????????????teacher?=>teacher.City,
??????????(student,?teacher)?=>new?{?老師姓名?=?teacher.First+teacher.Last,?城市?=?student.City,學生姓名=student.First+student.Last?});
????????????
????????????this.Response.Write("老師和學生都生活在同一城市的是:<br?/>");
????????????foreach?(var?obj?in?query)
????????????{
????????????????this.Response.Write(obj.老師姓名??+?","+?obj.城市+","+obj.學生姓名+"<br/>");
????????????}
???????
????????}
????}

轉載于:https://www.cnblogs.com/gwazy/archive/2007/12/14/994409.html

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