Caching jQuery variables

Question

I just read that if you are referring to the same DOM element over and over in a function it is better to cache them in a local variable like :

var btn = $('#clearBtn');

I have followed this where necessary but when accessing back this object I have always used $(btn).somemethod(); although we can access this directly like btn.somemethod();

I just need to know whether this will have a negative impact ?

You make an unnecessary function call. It's not "harmful", just unnecessary. You wouldn't do $($('#clearBtn')) either, would you? — Felix Kling
– Felix Kling, Commented Aug 24, 2013 at 7:10

Blender · Accepted Answer · 2013-08-24 06:49:06Z

2

There's no point in passing the jQuery object through the jQuery constructor. It's just wasteful. If the dollar sign looks nice to you, just prepend it to the variable name and use $btn in place of $(btn):

var $btn = $('#clearBtn');

answered Aug 24, 2013 at 6:49

Blender

300k55 gold badges462 silver badges511 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

codeGEN Over a year ago

I have very little knowledge on how internal processes take place within the jQuery lib. Do you mean that it runs unnecessary functions and waste resources?

Blender Over a year ago

@crazyMAN: $ is a function. You run it unnecessarily by passing btn to it.

Yossi Shasho · Accepted Answer · 2013-08-24 06:49:25Z

0

btn.somemethod(); will work, and is the correct way, since btn is already a jQuery object.

Besides, unless you call $('#clearBtn'); a lot of times in a short period of time, I wouldn't bother caching it.

answered Aug 24, 2013 at 6:49

Yossi Shasho

3,65033 silver badges47 bronze badges

Collectives™ on Stack Overflow

Caching jQuery variables

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related