In this section, we will learn what the Set entries() method is and how to use it in JavaScript.
What is JavaScript Set entries() Method?
Each value that we put in a `Set` object is considered as one entry. So via the `entries()` method, we can get an iterator object that contains the entire entries of the target `Set` object.
Note: In the Iterator section we’ve explained in greater details how to work with iterators, but in short, one way to get the contents of such an object is to use the `for of` loop. Basically, the `for of` will loop through all the content of the target iterator object and return all the entries one at a time.
JavaScript Set entries() Method Syntax:
entries();
entries() Function Parameters:
The method does not take an argument.
entries() Function Return Value:
The return value of this method is an iterator object that contains all the entries of the target Set object.
Example: using Set entries() method in JavaScript
const collect = new Set();
collect.add("Jack");
collect.add("Jack");
collect.add("Omid");
collect.add("John");
collect.add(100);
collect.add(200);
for (const entry of collect.entries()){
console.log("***");
console.log(`The entry is: ${entry}`);
console.log(`The key of this entry is: ${entry[0]} and the value is: ${entry[1]}`);
}
Output:
*** The entry is: Jack,Jack The key of this entry is: Jack and the value is: Jack *** The entry is: Omid,Omid The key of this entry is: Omid and the value is: Omid *** The entry is: John,John The key of this entry is: John and the value is: John *** The entry is: 100,100 The key of this entry is: 100 and the value is: 100 *** The entry is: 200,200 The key of this entry is: 200 and the value is: 200
Notes:
- Each of the entries that we get back from the `entries()` method is essentially an array of only two elements. The first and the second elements of this array are the same.
- Note: the `entries()` method is used in `Map` and `Array` objects as well. In those objects, the first and the second argument are `keys` and `values` respectively. So making this method behave similarly in the `Set` object as well, the committee used the same structure except the first and the second arguments are values. This is basically for creating a consistent API.
