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Jeremy Frimond
14,470 PointsGeneral JS Question on Arrays
When creating an array with the syntax new Array(argument), what is the argument passed to Array?
1 Answer
Dino Paškvan
Courses Plus Student 44,108 PointsWhen using the constructor to create an array (new Array(arg)), there are two possible types of argument(s).
If there is only a single argument, and it's an integer, it will create an array with a length set to that integer:
var myArr = new Array(5);
console.log(myArr);
// output: [undefined, undefined, undefined, undefined, undefined]
If instead you list several arguments, it will create an array and treat those arguments as array elements:
var firstElement = 5;
var secondElement = "text";
var thirdElement;
var myArr2 = new Array(firstElement, secondElement, thirdElement);
console.log(myArr2);
// output: [5, "text", undefined]