This post will describe the data structure in JavaScript that is equivalent to the C# HashSet.

**What is the JavaScript Equivalent to a C# HashSet?**

A JavaScript “**Set**” is equivalent/same as a HashSet in C#. A JavaScript Set is a collection of unique/distinct values. Only one instance of each value is allowed in a Set. More specifically, a Set can contain any data type value, including object references or primitive values.

**Syntax**

For creating a Set in JavaScript, use the below syntax:

**“Set” Methods to Perform Various Operations**

There are several ways to use the “**Set**” data structure in JavaScript to carry out different tasks.

**add() method**: It is used to add new elements in a Set. If the same element/object is already present in the Set, it does not add it again.**delete() method**: For deleting any specified element, use the “**delete()**” method. After deleting, it outputs “**true**”.**clear() method**: It removes/eliminates all elements from a Set.**has() method**: For verifying whether the element exists in the Set or not, use the “**has()**” method.**size**: It gives the number of all the existing elements of the Set.

**Example 1: Add Elements in Set**

Create a new Set using the “**new Set()**” constructor:

Call the add() method to add elements in Set:

jsSet.add(20);

jsSet.add(14);

jsSet.add(23);

jsSet.add(11);

jsSet.add(11);

As you can see, we have added six elements in Set, but the output shows the “**5**” elements because Set does not contain duplicate values:

**Example 2: Delete an Element From Set**

Here, we will delete “**14**” from Set using the “**delete()**” method:

The output shows “**true**”, which means “**14**” is successfully deleted from Set:

**Example 3: Check if Set Contains Specific Element**

Now, check whether “**14**” exists in Set or not. For that, call the “**has()**” method:

Output displays “**false,**” which means “**14**” is deleted from the created jsSet:

**Example 4: Remove All Elements From Set**

For removing all the elements from Set, use the “**clear()**” method:

**Example 5: Check Set Size**

Check the size of the Set using the “**size**” property:

The output shows “**0**”, which means all the elements of the Set are deleted:

That’s all about the JavaScript Sets.

**Conclusion**

A JavaScript “**Set**” is equivalent/same to a C# HashSet. HashSet is an unordered group of unique/distinct elements in C#. Similarly, the Set is a collection of unique values in JavaScript. Only one instance of each value is allowed in a Set. This post described the data structure in JavaScript that is equivalent to the C# HashSet.