How to copy/clone a hash/object in JQuery?

Question

I have a simple object (or hash) in Javascript:

var settings = {   link: 'http://example.com',   photo: 'http://photos.com/me.jpg' }; 

I need a copy of it. Is there a settings.clone() type method that will give me another object with the same attributes? I'm using jQuery, so happy to use a jQuery utility method if one exists.

Answer 1

Yes, extend an empty object with the original one; that way, everything will simply be copied:

var clone = $.extend({}, settings); 

---

Extending some filled object with another, e.g.:

$.extend({a:1}, {b:2}) 

will return:

{a:1, b:2} 

---

With the same logic:

$.extend({}, {foo:'bar', test:123}) 

will return:

{foo:'bar', test:123} 

i.e. effectively a clone.

Answer 2

In a non jQuery way.

var newObj = {};  Object.keys(settings).forEach(function(key) {      newObj[ key ] = settings[ key ]; });  

This copies only the top-level properties. To copy hashes with nested objects as property values, you will need to use a recursive function.

NB: The Object.keys(settings) avoids the need for calling settings.hasOwnProperty(key).