LinqtoSQL过滤器和语法顺序
时间:2020-03-06 14:56:45 来源:igfitidea点击:
我的Techie Bretheren(当然还有Sisteren!),
我有一个具有以下实体的LinqToSql数据模型:
数据模型http://danimal.acsysinteractive.com/images/advisor.jpg
我需要检索特定办公室的所有顾问,并按他们在办公室中的顺序排序。我已经有了与联接一起工作的第一部分:
public static List<Advisor>GetOfficeEmployees(int OfficeID)
{
List<Advisor> lstAdvisors = null;
using (AdvisorDataModelDataContext _context = new AdvisorDataModelDataContext())
{
var advisors = from adv in _context.Advisors
join advisoroffice in _context.OfficeAdvisors
on adv.AdvisorId equals advisoroffice.AdvisorId
where advisoroffice.OfficeId == OfficeID
select adv;
lstAdvisors = advisors.ToList();
}
return lstAdvisors;
}
但是,我似乎无法将我的疲倦的大脑包裹在order by子句的周围。任何人都可以提出一些建议吗?
解决方案
from adv in _context.Advisors where adv.OfficeAdvisor.Any(off => off.OfficeId == officeID) order adv by adv.OfficeAdvisor.First(off => off.OfficeId = officeID).Sequence select adv;
public static List<Advisor>GetOfficeEmployees(int OfficeID)
{
List<Advisor> lstAdvisors = null;
using (AdvisorDataModelDataContext _context = new AdvisorDataModelDataContext())
{
var advisors = from adv in _context.Advisors
join advisoroffice in _context.OfficeAdvisors
on adv.AdvisorId equals advisoroffice.AdvisorId
where advisoroffice.OfficeId == OfficeID
group adv by adv.OfficeId into g
order by g.Sequence
select g;
lstAdvisors = advisors.ToList();
}
return lstAdvisors;
}
注意:我目前无法在Visual Studio上对此进行测试,但应该可以使用。
我们可以像这样添加order by子句:
var advisors = from adv in _context.Advisors
join advisoroffice in _context.OfficeAdvisors
on adv.AdvisorId equals advisoroffice.AdvisorId
where advisoroffice.OfficeId == OfficeID
orderby advisoroffice.Sequence // < -----
select adv;

