Retrieve data from the nested list-CodePudding

How can I get all data from a nested list in C#?

Each person can have multiple cars.

Now I have a list of people and each item has a list of cars.

public class Person
{
    public string FullName { get; set; }
    public List<Car> Cars { get; set; }
}

public class Car
{
    public string Name { get; set; }
}

And values:

var people = new List<Person>()
{
    new Person()
    {
        FullName = "Jack Lee",
        Cars = new List<Car>()
        {
            new Car()
            {
                Name = "BMW"
            },
            new Car()
            {
                Name = "Tesla"
            }
        }
    },
    new Person
    {
        FullName = "Micheal doug",
        Cars = new List<Car>()
        {
            new Car()
            {
                Name = "Ferrari"
            }
        }
    }
};

What is the best way to get all car names with one query?

Is it possible to get all cars with one query?

CodePudding user response：

With System.Linq, you can use .SelectMany() to flatten the Cars lists from the people list and get the Name.

using System.Linq;

var result = people.SelectMany(x => x.Cars)
    .Select(x => x.Name)
    .ToList();

Demo @ .NET Fiddle