JavaScript arrays braces vs brackets

What is the difference between each of the following array definitions.

var myArray = [];
v开发者_JS百科ar myArray = {};
var myArray = new Array();

The first and third are equivalent and create a new array. The second creates a new empty object, not an array.

var myArray = []; //create a new array
var myArray = {}; //creates **a new empty object**
var myArray = new Array(); //create a new array

var myObject = {}; is equivalent to var myObject = new Object();

So, the second example is not an Array but a general Object.

This can get confusing as Array is a class and Object is a class - more precisely Array is a sub-class of Object. So, by and large, Object semantics are applicable to an Array:

var o = [];
o.push('element1');
o.push('element2');
o['property1'] = 'property value';  // define a custom property.
console.log(o.property1);
console.log(o.length);  // Outputs '2' as we've only push()'ed two elements onto the Array