Similar Question:
Understanding the difference between "new Array()" and "[]" in JavaScript array declaration
When working with JavaScript, you have the option to create a new array using:
var arr = new Array();
or simply using:
var arr2 = [];
What distinctions exist between these two methods, and in what scenarios would you opt for one over the other?
When using <code>new Array(2), you are creating an array with a size of 2, but it contains two undefined values. On the other hand, [2] creates an array with a size of 1, containing the number 2. In my opinion, using new Array doesn't align with the essence of JavaScript, despite it potentially simplifying array creation. Whether this matters or not depends on personal preference. Personally, I prefer using literals for all applicable types in JavaScript, especially for maintaining large projects exceeding 30-50 KLOC.
edit Experienced JavaScript programmers tend to steer clear of the new Array syntax due to the following reasons:
(new Array(X)).length == 1 for any X unless typeof(X) != "number"Yet another small reason for choosing to use [] over new Array() is the possibility that Array could be modified (although I have never personally witnessed this), whereas [] will always function as expected.
Array = "something";
var a = new Array(); // Fails
var b = []; // Works
In my opinion, they are exactly the same. I always prefer not to use new Array();
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