In this post of JQuery, I will introduce you to universal selector, represented by * symbol.
It is used to select all the elements in the html page.
Below is an example
1 <html>
2 <head>
3 https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js
4 </head>
5 <body>
6
7 function selectAll() {
8 var $all = $('*');
9 alert($all);
10 }
11
12 <input name="button" type="button" value="button" onclick="selectAll();"/>
13 </body>
14 </html>
In the above html code, on click of button I am calling javascript selectAll method.
In the javascript method, I am selecting all the elements from beginning of head tag to end of it, using the below code
$('*')
Or
jQuery('*')
jQuery or its alias ‘$’ symbol is a function that accepts two arguments. The first argument is ‘selector’ and second one is a ‘context’ (optional).
‘selector’ defines a criteria which is used to identifies the elements to be returned and ‘context’ gives selector the scope of the document within which
the selector has to select the elements meeting the criteria.
The function returns an object which is collection of DOM elements matching the criteria.
The selector in the above example is ‘*’ which selects all the elements within the context and in this case absence of context indicates the whole document as the context.