Csharp/CSharp Tutorial/LINQ/Nested Query

An untidy nested query

using System;
using System.Collections.Generic;
using System.Linq;
public class MainClass {
    public static void Main() {
        string[] names = { "Tom", "Dick", "Harry", "Mary", "Jay" };
        IEnumerable<string> query =
          Enumerable.Select(
            Enumerable.OrderBy(
              Enumerable.Where(
                names, n => n.Contains("a")
              ), n => n.Length
            ), n => n.ToUpper()
          );
    }
}

Nested query list

using System;
using System.Collections;
using System.Collections.Generic;
using System.Text;
using System.Linq;
using System.Reflection;
class Person {
    int _id;
    int _idRole;
    string _lastName;
    string _firstName;
    public int ID {
        get { return _id; }
        set { _id = value; }
    }
    public int IDRole {
        get { return _idRole; }
        set { _idRole = value; }
    }
    public string LastName {
        get { return _lastName; }
        set { _lastName = value; }
    }
    public string FirstName {
        get { return _firstName; }
        set { _firstName = value; }
    }
}
class Role {
    int _id;
    string role;
    public int ID {
        get { return _id; }
        set { _id = value; }
    }
    public string Role {
        get { return role; }
        set { role = value; }
    }
}
class Program {
    static void Main(string[] args) {
        List<Person> people = new List<Person> {
               new Person { ID = 1, IDRole = 1, LastName = "A", FirstName = "B"},
               new Person { ID = 2, IDRole = 2, LastName = "G", FirstName = "T"},
               new Person { ID = 3, IDRole = 2, LastName = "G", FirstName = "M"},
               new Person { ID = 4, IDRole = 3, LastName = "C", FirstName = "G"}
            };
        List<Role> roles = new List<Role> {
               new Role { ID = 1, Role = "Manager" },
               new Role { ID = 2, Role = "Developer" }
            };
        var query = people
                    .Where(p => p.ID == 1)
                    .SelectMany(p => roles
                                    .Where(r => r.ID == p.ID)
                                    .Select(r => new { p.FirstName, p.LastName, r.Role }));
    }
}