嵌套条件运算

Question

使用VS 2013（不是C＃6.0还）

我有以下的LINQ其工作原理：

var radData = (from stop in dbContext.stop_details 
       join del in dbContext.stop_event on stop.id equals del.stop_id into Inners 
       from sd in Inners.DefaultIfEmpty() 
       where stop.ship_date == startDate && stop.cust_ref_5_terminalID == "HEND" 
       select new 
       { 
        shipDate = stop.ship_date, 
        custRef = stop.cust_ref_5_terminalID, 
        name = stop.customer.customer_name, 
        ontime = (int?)sd.ontime_performance, 
        OTP = ((int?)sd.ontime_performance) < 1 ? "Ontime" : "Late" 
       }).ToList(); 

但OTP需求价值为以下取决于ontime_performance：

• 空 - “打开”
• < 1 “龙泰”
• 1 “晚一天”
• 2 “两天迟到”
• “> 2 “的三个或更多日晚”

有没有办法窝呢？到目前为止，我没有尝试过任何工作..

谢谢。

Answer 1

你可以连许多?:如下：

var radData = (from stop in dbContext.stop_details 
       join del in dbContext.stop_event on stop.id equals del.stop_id into Inners 
       from sd in Inners.DefaultIfEmpty() 
       where stop.ship_date == startDate && 
        stop.cust_ref_5_terminalID == "HEND" 

       let value = ((int?)sd.ontime_performance) 
       select new 
       { 
        shipDate = stop.ship_date, 
        custRef = stop.cust_ref_5_terminalID, 
        name = stop.customer.customer_name, 
        ontime = (int?)sd.ontime_performance, 
        OTP = value == null ? "Open" : 
         value < 1 ? "On time" : 
         value == 1 ? "One Day Late" : 
         value == 2 ? "Two Days Late" : "Three or more days late" 
       }).ToList(); 

您也可以在现场存储在一个变量，所以你不需要每次都投它：let value = ((int?)sd.ontime_performance)

BTW - 现场您可以将value < 1更改为value == 0。与其他条件相一致，不易混淆