如何獲取此條件包含投影來實例化ref_calendar_premis實體對象的「premis」實體 - 對象屬性？

我正在處理我的第一個EntityFramework解決方案，我很難過。如何獲取此條件包含投影來實例化ref_calendar_premis實體對象的「premis」實體 - 對象屬性？

當我遍歷生成的「日曆」實體對象時，屬性calendar.ref_calendar_premisis.premisis未實例化（null）。我明白爲什麼，我停用延遲加載，因爲我想控制條件「包括」在語法樹投影像這樣：

private List<CalendarBlockDTO> FillUserCalendar(DateTime start, DateTime end, int uid, bool everything) 
    { 
     var result = new List<CalendarBlockDTO>(); 

     using (var db = new ViggoEntities()) 
     { 
      //We need to disable lazyloading to use the "expression tree" syntax 
      db.Configuration.LazyLoadingEnabled = false; 

      //flip our "everything" so we can compare it to our "special" column 
      int specialScope = Convert.ToInt32(!everything); 

      //Build a query "Projection" with "expression tree" syntax 
      var query = from c in db.calendars 
         select new 
          { 
           calendarEntry = c, 

           createdByUser = c.MadeByUser, 

           premisesBookings = c.ref_calendar_premises.Where 
           (
            rcp => rcp.deleted == 0 && 
            (
              //started before the start-parameter AND ended after start-parameter 
             (rcp.timestart < start && rcp.timeend > start) || 
              //OR startet before the end-parameter AND ended after the end-parameter 
             (rcp.timestart < end && rcp.timeend > end) || 
              //OR startet before the start-parameter AND ended after the end-paremeter 
             (rcp.timestart < start && rcp.timeend > end) || 
              //OR startet after the start-parameter AND ended before the end-parameter 
             (rcp.timestart > start && rcp.timeend < end) 
            ) 
           ), 

           attendingGroups = c.ref_groups_calendar.Where 
           (
            rug => rug.deleted == 0 
           ), 

           groups = c.ref_groups_calendar.Select(rgc => rgc.usergroup), 

           ////Assignments not implemented yet 
           ////assignments = c. 

           schedules = c.ref_calendar_schedule.Where 
           (
            sch => sch.deleted == 0 
           ) 
          }; 

      var calEntries = 
       query.ToArray().Select(c => c.calendarEntry). 
       Where(
         //If only special requested, show only special 
         c => c.special >= specialScope && 
         //If not "MadeInInfo", show for creator as well 
         (c.madeininfo==0 && c.made_by == uid) || 
         //Else, show to involved users 
         (c.ref_groups_calendar.Any(rgc => rgc.usergroup.ref_users_groups.Any(rug => rug.userid == uid))) 
         ); 

      foreach (var calendar in calEntries) 
      { 
       //I WANT THIS TO NOT THROW AN EXCEPTION, PREMIS SHOULD NOT BE NULL 
       if (calendar.name == "Dinner with Allan" && calendar.ref_calendar_premises.Any(rcp => rcp.premis == null)) 
        throw new Exception("Premis not instantiated!"); 

       result.AddRange(CalendarToCalendarBlockDTOs(calendar)); 
      } 
     } 

     return result; 
    }

我嘗試添加類似：

... 
room = c.ref_calendar_premises.Select(r => r.premis), 
...

..但無濟於事。我們的測試數據中預訂了一個房間，用於「與艾倫一起吃晚餐」活動，但我似乎無法獲得它加載premis-entyties。我沒有以前的EntityFramework，LINQ to SQL或任何其他ORM的經驗，所以我可能會漏掉一些明顯的東西。

有什麼建議嗎？

來源

2012-12-16 Julian

'premis'是一種集合類型嗎？ – Slauma

不，是實體類「premisis」的對象 – Julian

有趣的是，你說「包括」但不使用'c.ref_calendar_premises.Include（r => r.premis）'。 –

我扭曲了我們的DB負責人的手臂，並且由於轉換錯誤（我正在查看testdata文檔，而不是實際數據），因此所有行的premisisid都爲null。非常感謝您的投入和您的時間，我只是表明我自己0_0

來源

2012-12-17 10:45:57 Julian

如何獲取此條件包含投影來實例化ref_calendar_premis實體對象的「premis」實體 - 對象屬性？

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