Sets in C#

Sets in C# is a HashSet. HashSet in C# eliminates duplicate strings or elements in an array. In C#, it is an optimized set collection

To declare HashSet −

var h = new HashSet<string>(arr1);

Above, we have set the already declared array arr1 in the HashSet.

Now set it on the array to remove the duplicate words −

string[] arr2 = h.ToArray();

Let us see an example to remove duplicate strings using C# HashSet.

Here, we have duplicate elements −

Example

using System;
using System.Collections.Generic;
using System.Linq;

class Program {
   static void Main() {
      string[] arr1 = {"Table","Chair","Pen","Clip","Table"};
      Console.WriteLine(string.Join(",", arr1));

      // HashSet
      var h = new HashSet<string>(arr1);

      // eliminates duplicate words
      string[] arr2 = h.ToArray();
      Console.WriteLine(string.Join(",", arr2));
   }
}