中內部聯接拋出異常

Question

我不知道爲什麼，這並不工作（會引發內部異常）。有人可以幫忙嗎？

var flightCrew = from crew in crews 
     medium inner join flight in flights on crew.Model equals flight.Model 
     into schedule from flight in schedule.active() 

Answer 1

我不知道什麼是地球上的一箇中等內連接。我認爲你的意思是左派加入？試試這個：

var flightCrew = from crew in crews 
        join flight in flights on crew.Model equals flight.Model 
        into schedule from flight in schedule.DefaultIfEmpty() 
        select new 
         { 
          //the following are sample fields 
          crew.CrewId, 
          crew.Name, 
          FlightName = flight != null ? flight.Name : "" 
         } 

注意，無論字段你從flight得到，你會有執行對空校驗。