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JavaScript

Posted by Steven Chung
Steven Chung
1,277 Points

What is the function of the '.' when calling the 'warning' class? (e.g. $('.warning'))

The ending snippet is as follows:

$('.warning').hide().show('slow');

What is the function of the period ('.') before warning? Is this a search function of sorts?

3 Answers

0yzh 󠀠
0yzh 󠀠
17,276 Points
0yzh 󠀠
0yzh 󠀠
17,276 Points

Hello Steven,

In this jQuery code, the '.' before warning is like saying you are selecting an element by it's class. Since classes are associated with '.' and id's with '#', this is how you select elements in jQuery.

class = $('.warning').hide().show('slow');

id = $('#warning').hide().show('slow');

hope this helps.

Julian Gutierrez
Julian Gutierrez
19,325 Points
Julian Gutierrez
Julian Gutierrez
19,325 Points

In JQuery one can target an element by using selectors similar to css. Here the '.' means that you are targeting an element with the class of warning. If you were needing to target an element with the id of warning you would use

$("#warning")
Joe Hartman
Joe Hartman
20,881 Points
Joe Hartman
Joe Hartman
20,881 Points

The dot tells jQuery to select any element with a class of "warning" and then do something with it. It's the same way you'd write a warning class selector in a CSS file. Many jQuery selectors mirror the format used in CSS.