JavaScript Reference

Quick Reference

The Array.from() method returns an array from any object with a length property.

<!-- html element to place output -->
<p id='my_alphabet'></p>
// string
let letters = 'tuvwxyz'

// new array
let my_alpha = Array.from(letters);

// create the new array and output it to the HTML element
document.getElementById('my_alphabet').innerHTML = my_alpha;

The way this works (see Syntax section below):

  • The Array.from() method cycles through an iterable object such as a string and places each item in an array

Note

Arrays count starting from zero NOT one. So item 1 is position [0], item 2 is position [1], and item 3 is position [2] … and so on.

Output

t,u,v,w,x,y,z

Syntax

Array.from(object, mapFunction, thisValue)

Parameters

ParameterDescription
objectThe object to convert to an array (required)
mapFunctionA map function to call on each item
thisValueA value to use as "this" for the mapFunction

JavaScript Notes:

  • When using JavaScript, single or double quotation marks are acceptable and work identically to one another; choose whichever you prefer, and stay consistent
  • JavaScript is a case-sensitive language; firstName is NOT the same as firstname
  • Arrays count starting from zero NOT one; so item 1 is position [0], item 2 is position [1], and item 3 is position [2] … and so on
  • JavaScript variables must begin with a letter, $, or _
  • JavaScript variables are case sensitive (x is not the same as X)

We’d like to acknowledge that we learned a great deal of our coding from W3Schools and TutorialsPoint, borrowing heavily from their teaching process and excellent code examples. We highly recommend both sites to deepen your experience, and further your coding journey. We’re just hitting the basics here at 1SMARTchicken.