Question

I have those classes:

public class Flight
{
    public string FlightNum { get; set; }
    public List<Pax> Pax { get; set; }
}

public class Pax
{
    public string PaxName { get; set; }
    public string PaxSurName { get; set; }
}

I want to filter flight so that it will only contain flights whose passenger’s name is a certain string
I tried:

var paxList = flights.Where(f => f.Pax.Where(p => p.PaxName == "d"));

The above code didn’t work…
e.g: I want to this in a SINGLE Lambda expression

Answer 1

Where needs a function that returns a boolean.

var paxList = flights.Where(f => f.Pax.Any(p => p.PaxName == "d"));

The nested expression f.Pax.Any(p => p.PaxName == "d") will return true if any p matches the criterion that PaxName is exactly "d".

And hence the resulting list will be of flights (not passengers) which contain any passenger meeting that criterion. I mention this because paxList is potentially not a good variable name.