code that i have to do it through LINQ

I have a code that i have to do it through LINQ

var airlineNameList = new List<string>();

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

How can do it through LINQ. Note: contract_ is the o开发者_如何学Gobject of class.

Please Help..

---

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

---

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

Don't you also need Distinct?

---

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

The C# foreach does implicit casting for you (which is yuck), so perhaps you need this:

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