Linq 左右连接

标签：ar   new   sql   ef   on   sp   text   rom   

---左连接  （转载）

DataClasses1DataContext db = new DataClasses1DataContext();
var leftJoinSql = from student in db.Student
join book in db.Book on student.ID equals book.StudentID into temp
from tt in temp.DefaultIfEmpty()
select new
{
sname= student.Name,
bname = tt==null?"":tt.Name//这里主要第二个集合有可能为空。需要判断
};

---右连接

DataClasses1DataContext db=new DataClasses1DataContext();
var rightJoinSql = from book in db.Book
join stu in db.Student on book.StudentID equals stu.ID into joinTemp
from tmp in joinTemp.DefaultIfEmpty()
select new {
sname=tmp==null?"":tmp.Name,
bname=book.Name

};

Linq 左右连接,布布扣,bubuko.com

Linq 左右连接

标签：ar   new   sql   ef   on   sp   text   rom   

原文地址：http://www.cnblogs.com/yanhu/p/3916545.html