How to join two string arrays and extract matching strings

How to join two string arrays and extract matching strings:

For example: You have the following two string arrays and you want extract the matching strings from both. Then through LINQ you can do this: In this particular example “this”, “is” and “LINQ” are same in both strings.

string[] str = new string[] { "hello", "world" , "this", "is", "LINQ" };

string[] str2 = new string[] { "this", "is" , "C#", "LINQ", "query" };

Code

In the query: joining each string from str on each string of str2 and in the end, if found match strings from both then put them in a list.

   List<string> query =

          (from string st in str

           join s in str2 on st equals s

           select s).ToList();

Displaying the list:

           foreach (var item in query)

           {

               Console.WriteLine(item.ToString());

           }

Output of the program is:

              this

               is

       LINQ

ANOTHER WAY THROUGH SIMPLE FOR LOOPS:

Create a new string where to hold the match values from both string arrays:

   string[] st = new string[10]; 

   int k = 0;

    for (int i = 0; i < str.Length; i++)

    {

        for (int j = 0; j < str2.Length; j++)

         {

              if (str[i].Equals(str2[j]))

              {

                  st[k] = str[i];

                  k++;

              }

        }

             

   }

Displaying the new string array:

           for (int i = 0; i < k; i++)

           {

               Console.WriteLine(st[i]);

           }

Output of the program is:

              this

               is

       LINQ