using static System.Console;

using System.Linq;

using System.Collections.Generic;

​

class Customer {

    public int ID { get; set; }

    public string Name { get; set; }

}

​

class Order {

    public int ID { get; set; }

    public string Product { get; set; }

}

​

public static class Program {

    public static void Main() {

        // Example customers.

        var customers = new Customer[] {

            new Customer{ID = 5, Name = "Sam"},

            new Customer{ID = 6, Name = "Dave"},

            new Customer{ID = 7, Name = "Julia"},

            new Customer{ID = 8, Name = "Sue"}

        };

        // Example orders.

        var orders = new Order[] {

            new Order{ID = 5, Product = "Book"},

            new Order{ID = 6, Product = "Game"},

            new Order{ID = 7, Product = "Computer"},

            new Order{ID = 8, Product = "Shirt"}

        };

        // Join on the ID properties.

        var query = from c in customers

                join o in orders on c.ID equals o.ID

                select new { c.Name, o.Product };

​

        WriteLine(query.GetType());

​

        // Display joined groups.

        foreach (var group in query) {

            WriteLine("{0} bought {1}", group.Name, group.Product);

        }

        var lista = query.ToList();

        WriteLine(lista.GetType());

        //criando explicitamente uma lista de string (neste caso é possível)

        var query2 = from c in customers

                join o in orders on c.ID equals o.ID

                select new List<string> { c.Name, o.Product };

​

        WriteLine(query2.GetType());

​

​

        foreach (var group in query2) {

            WriteLine("{0} bought {1}", group[0], group[1]);

        }

        var lista2 = query2.ToList();

        WriteLine(lista2.GetType());

    }

}