代码，我必须通过LINQ

Question

做到这一点我有我必须这样做，通过LINQ

var airlineNameList = new List<string>(); 

foreach (DTTrip trip in contract_.Trips) 
{ 
    foreach (DTFlight flight in trip.ListOfFlights) 
    { 
     airlineNameList.Add(flight.AirLineName); 
    } 
} 

如何通过LINQ做一个代码。 注意：contract_是类的对象。

请帮助..

Answer 1

var resultList = contract_.Trips 
     .Cast<DTTrip>() 
     .SelectMany(trip => trip.ListOfFlights.Cast<DTFlight>()) 
     .Select(flight => flight.AirLineName) 
     .ToList(); 

难道你还需要Distinct？

Answer 2

var airlineNameList = contract_.Trips 
           .SelectMany(t => t.ListOfFlights) 
           .Select(f => f.AirLineName); 

Answer 3

var airlineNameList = (
    from trip in contract_.Trips 
    from flight in trip.ListOfFlights 
    select flight.AirLineName) 
    .ToList(); 

的C＃的foreach为你所做的隐式转换（这是呸），所以也许你需要这个：

var airlineNameList = (
    from trip in contract_.Trips.Cast<DTTrip>() 
    from flight in trip.ListOfFlights.Cast<DTFlight>() 
    select flight.AirLineName) 
    .ToList();