017 LINQ Join

The Join operator join more than one collection and return a new collection that contains elements supplied collections that satisfies specified expression.

Below is the example of  LINQ Join using LINQ query.

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using System;

using System.Collections.Generic;

using System.Data.SqlClient;

using System.Data.Sql;

using System.Data;

using System.Linq;

using System.Collections;

using System.Xml;

using System.Xml.Linq;

using System.IO;

namespace ConsoleApplication1

{

               class Program

                {

                   static void Main(string[] args)

                   {

                     var students = new student[]

                    {

                        new student{name = "John1",roll=123,age=12},

                        new student{name = "John2",roll=124,age=13},

                        new student{name = "John3",roll=125,age=14},

                        new student{name = "John4",roll=126,age=15},

                        new student{name = "John5",roll=127,age=16},

                        new student{name = "John6",roll=128,age=17},

                        new student{name = "John7",roll=129,age=18}

                   };

                   var students2 = new student2[]

                   {

                     new student2{address = "12,ABC Road",roll=123},

                     new student2{address = "13,ABC Road",roll=124},

                     new student2{address = "14,ABC Road",roll=125},

                     new student2{address = "15,ABC Road",roll=131},

                     new student2{address = "16,ABC Road",roll=132},

                     new student2{address = "17,ABC Road",roll=133},

                     new student2{address = "18,ABC Road",roll=134}

                    };

                    var query = from a in students

                                        join b in students2 on a.roll equals b.roll

                                        select new { a.name,a.roll,b.address };

                   foreach (var obj in query)

                   {

                           Console.WriteLine("Name :{0} Roll : {1} Address : {2}", obj.name, obj.roll, obj.address);

                   }

                     Console.ReadKey();

           }

      }

}

public class student

{

               public string name { get; set; }

               public int roll { get; set; }

               public int age { get; set; }

}

public class student2

{

                public string address { get; set; }

                public int roll { get; set; }

}

Name :John1 Roll : 123 Address : 12,ABC Road
Name :John2 Roll : 124 Address : 13,ABC Road
Name :John3 Roll : 125 Address : 14,ABC Road
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Below is the example of  LINQ Join using lambda expression.



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using System;

using System.Collections.Generic;

using System.Data.SqlClient;

using System.Data.Sql;

using System.Data;

using System.Linq;

using System.Collections;

using System.Xml;

using System.Xml.Linq;

using System.IO;

namespace ConsoleApplication1

{

          class Program

          {

              static void Main(string[] args)

              {

                 var students = new student[]

                      {

                                  new student{name = "John1",roll=123,age=12},

                                  new student{name = "John2",roll=124,age=13},

                                  new student{name = "John3",roll=125,age=14},

                                  new student{name = "John4",roll=126,age=15},

                                  new student{name = "John5",roll=127,age=16},

                                  new student{name = "John6",roll=128,age=17},

                                  new student{name = "John7",roll=129,age=18}

                      };

               var students2 = new student2[]

               {

                                new student2{address = "12,ABC Road",roll=123},

                                new student2{address = "13,ABC Road",roll=124},

                                new student2{address = "14,ABC Road",roll=125},

                                new student2{address = "15,ABC Road",roll=131},

                                new student2{address = "16,ABC Road",roll=132},

                                new student2{address = "17,ABC Road",roll=133},

                                new student2{address = "18,ABC Road",roll=134}

            };

                     var query = students.Join(students2,

                                a => a.roll,

                                b => b.roll,

                               (a, b) => new { a.name, a.roll, b.address });

                  foreach (var obj in query)

                  {

                             Console.WriteLine("Name :{0} Roll : {1} Address : {2}", obj.name, obj.roll, obj.address);

                  }

               Console.ReadKey();

          }

     }

}

public class student

{

     public string name { get; set; }

     public int roll { get; set; }

     public int age { get; set; }

}

public class student2

{

     public string address { get; set; }

     public int roll { get; set; }

}

Name :John1 Roll : 123 Address : 12,ABC Road
Name :John2 Roll : 124 Address : 13,ABC Road
Name :John3 Roll : 125 Address : 14,ABC Road

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