Array functions in JavaScript part-1

A JavaScript array can:

  • Hold values of different types.
  • The length of an array is dynamically sized and auto-growing.

Most of the array functions are used to transform or manipulate an array in some way.

In this post we will cover the following array functions:

  • every()
  • Some()
  • sort()
  • filter()
  • join()

every():

Checks if every element of an array pass the test.

* * *

/ / checks every element in the array is greater than zero

let numbers = [1, 3, 5];

let result = numbers.every( e =>e > 0);

some():

Checks if at least one element in the array passes the test.

* * *

// checks at least one element in the array is less than five

let marks = [ 4, 5, 7, 9, 10, 3 1];

sort():

Sorts elements in place and returns the sorted array. Sorts the array in ascending order by default.

Casts elements to strings and compares them to determine the order.

* * *

const months = [“March’, ‘Jan’, ‘Feb’, ‘Dec’];

months.sort( );

console.log( months) ;

/ /output: Array [“Dec”, “Feb”, “Jan”, “March”]

let less Than Five = marks. some(e => e < 5);

filter():

Creates a new array with all elements that pas the test implemented by the provided function.

* * *

const words = [‘spray’, limit’, ‘elite’, ‘exuberant’,

destruction’ , ‘present ‘];

const result = words.filter (word =>Word.length> 6);

console. log( result) ;

/ /  output: Array [“exuberant”, “destruction”, “present “]

join():

Concatenates all elements of an array into a string separated by a separator.

* * *

const elements = [‘Fire’, ‘Air’, ‘Water’];

console. log(elements.join( ));

// output: “Fire , Air, Water”

console. log(elements.join(‘-‘));

// output: “Fire-Air-Water”

Leave a Reply

Your email address will not be published.