LINQ与MAX（），并加入

Question

有我使用

  var renewalQuery = from r in crnnsupContext.Renewals 
           from w in crnnsupContext.WorkPlaces 
           join p in crnnsupContext.ProvStates on p.ProvinceStateID equals r.EmployerProvState 
           where r.RegNumber == _username && r.PlaceOfWork == w.WorkID 
           select r; 

LINQ的声明有一个r.RenewalYear，我想获得最新的一年，所以我想是这样

   var renewalQuery = from r in crnnsupContext.Renewals 
           group r by r.RenewalYear into g 
           from w in crnnsupContext.WorkPlaces 
           join p in crnnsupContext.ProvStates on p.ProvinceStateID equals r.EmployerProvState 
           where r.RegNumber == _username && r.PlaceOfWork == w.WorkID 
           select g.max(r.RenewalYear); 

显然这不起作用，有没有人知道这个正确的语法？非常感谢

Answer 1

选择一年，然后在使用MAX（）：

var renewalQuery = (from r in crnnsupContext.Renewals 
           group r by r.RenewalYear into g 
           from w in crnnsupContext.WorkPlaces 
           join p in crnnsupContext.ProvStates on p.ProvinceStateID equals r.EmployerProvState 
           where r.RegNumber == _username && r.PlaceOfWork == w.WorkID 
           select r.RenewalYear).Max();