What is array literal notation in javascript and when should you use it?

javascript arrays jslint literals
Matt picture Matt · Jul 7, 2009 · Viewed 67.3k times · Source

JSLint is giving me this error:

Problem at line 11 character 33: Use the array literal notation [].

var myArray = new Array();

What is array literal notation and why does it want me to use it instead?

It shows here that new Array(); should work fine... is there something I'm missing?

Answer

CookieOfFortune picture CookieOfFortune · Jul 7, 2009

array literal notation is where you define a new array using just empty brackets. In your example:

var myArray = [];

It is the "new" way of defining arrays, and I suppose it is shorter/cleaner.

The examples below explain the difference between them:

var a = [],            // these are the same
    b = new Array(),   // a and b are arrays with length 0

    c = ['foo', 'bar'],           // these are the same
    d = new Array('foo', 'bar'),  // c and d are arrays with 2 strings

    // these are different:
    e = [3],             // e.length == 1, e[0] == 3
    f = new Array(3);   // f.length == 3, f[0] == undefined

Reference: What’s the difference between “Array()” and “[]” while declaring a JavaScript array?

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