LINQ 12 Concat

SQL has union and linq has concat, concat is a way to join multiple collections of elements

using System;

using System.Linq;

namespace pc.linq10

{

    class Program

    {

        static void Main(string[] args)

        {

            var nums = Enumerable.Range(0, 10);

            var chars = "Hello world".ToCharArray();

            var names = new string[] { "Pawel", "Magda", "Tomek" };

            var result1 = (from n in nums

                           select n.ToString())

                            .Concat(from c in chars

                                    select c.ToString())

                            .Concat(names);

            Array.ForEach(result1.ToArray(), n => Console.Write(n + ", "));

            Console.WriteLine();

            var result2 = nums.Select(n => n.ToString())

                .Concat(chars.Select(c => c.ToString()))

                .Concat(names);

            Array.ForEach(result2.ToArray(), s => Console.Write(s + ", "));

            Console.WriteLine();

        }

    }

}

We mentioned that not all method based linq statements have an expression based equivalent however this doesn't prevent us from using mixed syntax in our linq queries.