C# | Check if two HashSet<T> objects are equal

Last Updated : 11 Jul, 2025

Equals(Object) Method which is inherited from the Object class is used to check if a specified HashSet<T> object is equal to another HashSet<T> object or not. Syntax:

public virtual bool Equals (object obj);

Here, obj is the object which is to be compared with the current object. Return Value: This method return true if the specified object is equal to the current object otherwise it returns false. Below programs illustrate the use of above-discussed method: Example 1:

CSharp

// C# program to if a HashSet object
// is equal to another HashSet object
using System;
using System.Collections.Generic;

class Geeks {

    // Main Method
    public static void Main(String[] args)
    {

        // Creating a HashSet of strings
        HashSet<string> mySet = new HashSet<string>();

        // Inserting elements in HashSet
        mySet.Add("DS");
        mySet.Add("C++");
        mySet.Add("Java");
        mySet.Add("JavaScript");

        // Checking whether mySet is
        // equal to itself or not
        Console.WriteLine(mySet.Equals(mySet));
    }
}

Output:

True

Example 2:

CSharp

// C# program to if a HashSet object
// is equal to another HashSet object
using System;
using System.Collections.Generic;

class Geeks {

    // Main Method
    public static void Main(String[] args)
    {

        // Creating a HashSet of strings
        HashSet<string> mySet1 = new HashSet<string>();

        // Inserting elements in HashSet
        mySet1.Add("HTML");
        mySet1.Add("CSS");
        mySet1.Add("PHP");
        mySet1.Add("DBMS");

        // Creating a HashSet of integers
        HashSet<int> mySet2 = new HashSet<int>();

        // Inserting elements in HashSet
        for (int i = 0; i < 5; i++) {
            mySet2.Add(i * 2);
        }

        // Checking whether mySet1 is
        // equal to mySet2 or not
        Console.WriteLine(mySet1.Equals(mySet2));

        // Creating a HashSet of integers
        HashSet<int> mySet3 = new HashSet<int>();

        // Assigning mySet2 to mySet3
        mySet3 = mySet2;

        // Checking whether mySet3 is
        // equal to mySet2 or not
        Console.WriteLine(mySet3.Equals(mySet2));
    }
}