Introduction to JavaScript Sets

In JavaScript, a Set is a built-in object that allows you to store unique values of any type. It provides a collection of values without any specific order. Sets are useful when you want to store a collection of unique elements and perform operations such as adding, removing, or checking for the existence of values. In this article, we will introduce Sets in JavaScript and provide examples to illustrate their usage.

Creating a Set

You can create a Set in JavaScript by using the Set() constructor or by initializing it with an iterable object, such as an array. For example:

    
      var set1 = new Set();
      var set2 = new Set([1, 2, 3]);
    
  

Set Operations

Sets provide various methods for adding, removing, and checking the existence of values. Some commonly used methods include add(), delete(), has(), and size(). For example:

    
      var set = new Set();
      set.add(1);
      set.add(2);
      set.delete(1);
      console.log(set.has(2)); // true
      console.log(set.size);   // 1
    
  

Working with JavaScript Sets

JavaScript Sets provide several methods for performing operations on sets. These methods allow you to manipulate and iterate over the values stored in a Set. In this article, we will explore the commonly used methods and operations available with JavaScript Sets, along with examples.

Adding Values to a Set

To add values to a Set, you can use the add() method. This method adds a new element to the Set. For example:

    
      var set = new Set();
      set.add(1);
      set.add(2);
      set.add(3);
    
  

Removing Values from a Set

You can remove values from a Set using the delete() method. This method removes a specified element from the Set. For example:

    
      var set = new Set([1, 2, 3]);
      set.delete(2);
    
  

Iterating over a Set

Sets can be iterated using various iteration methods, such as forEach() and for-of loop. These methods allow you to perform operations on each element of the Set. For example:

    
      var set = new Set([1, 2, 3]);

      set.forEach(function(value) {
        console.log(value);
      });

      for (var value of set) {
        console.log(value);
      }
    
  

JavaScript Set Operations

JavaScript Sets provide various operations and methods to manipulate, combine, and compare sets. These operations include set union, intersection, difference, and subset checks. In this article, we will explore the different set operations available in JavaScript Sets, along with examples.

Set Union

The union of two sets contains all the unique elements from both sets. In JavaScript, you can perform set union using the Set() constructor and the add() method. For example:

    
      var set1 = new Set([1, 2, 3]);
      var set2 = new Set([3, 4, 5]);

      var unionSet = new Set(set1);
      set2.forEach(function(value) {
        unionSet.add(value);
      });
    
  

Set Intersection

The intersection of two sets contains the common elements present in both sets. In JavaScript, you can perform set intersection using the forEach() method and the delete() method. For example:

    
      var set1 = new Set([1, 2, 3]);
      var set2 = new Set([2, 3, 4]);

      var intersectionSet = new Set();

      set1.forEach(function(value) {
        if (set2.has(value)) {
          intersectionSet.add(value);
        }
      });
    
  

JavaScript Set Operations: Difference and Subset

JavaScript Sets provide additional operations, such as set difference and subset checks. These operations allow you to compare sets and determine their differences or check if one set is a subset of another. In this article, we will explore the set difference and subset operations in JavaScript Sets, along with examples.

Set Difference

The difference between two sets contains the elements that are present in the first set but not in the second set. In JavaScript, you can perform set difference using the forEach() method and the delete() method. For example:

    
      var set1 = new Set([1, 2, 3]);
      var set2 = new Set([2, 3, 4]);

      var differenceSet = new Set(set1);

      set2.forEach(function(value) {
        differenceSet.delete(value);
      });
    
  

Subset Check

To check if one set is a subset of another, you can use the every() method. This method checks if all elements of one set are present in another set. For example:

    
      var set1 = new Set([1, 2, 3]);
      var set2 = new Set([1, 2, 3, 4, 5]);

      var isSubset = set1.every(function(value) {
        return set2.has(value);
      });