LINQ到實體查詢（1對多）

Question

我需要建立一個查詢到實體獲得的記錄，包括：

• AssetWeapon，
• PersonOut
• 許多與IsIn = True記錄，
• 記錄數IsIn = False,
• 本月的名稱StartTime,

個

記錄應當由AssetWeapon

alt text http://www.freeimagehosting.net/uploads/4fee01b48c.png

Answer 1

分組也許這篇文章可以幫助你：

http://msdn.microsoft.com/en-us/vcsharp/aa336746.aspx

看投影算..

Answer 2

在這裏我得到了什麼最後：

var query = from ta in db.Transactions_Assets.Include("Transaction") 
         let items = new 
         { 
          Weapon = ta.AssetWeapon, 
          Month = ta.Transaction.StartTime.Value.Month, 
          IsIn = ta.IsIn 
         } 
         group items by items.Weapon into g 
         select new { 
          Weapon = g.Key, 
          MonthlyFlow = from m in g 
            group m by m.Month into mg 
            select new { Month = mg.Key, 
               Ins = mg.Count(x => x.IsIn == true), 
               outs = mg.Count(x => x.IsIn == false) 
            } 
         };