Java 'The Next Generation': jQuery Selection

jQuery selectors allow you to select and manipulate HTML elements as a group or as a single element.

jQuery Selectors

In the previous chapter we looked at some examples of how to select different HTML elements.

It is a key point to learn how jQuery selects exactly the elements you want to apply an effect to.

jQuery selectors allow you to select HTML elements (or groups of elements) by element name, attribute name or by content.

	In HTML DOM terms: Selectors allow you to manipulate DOM elements as a group or as a single node.

jQuery uses CSS selectors to select HTML elements.

$("p") selects all <p> elements.

$("p.intro") selects all <p> elements with class="intro".

$("p#demo") selects the first <p> element with id="demo".

jQuery uses XPath expressions to select elements with given attributes.

$("[href]") select all elements with an href attribute.

$("[href='#']") select all elements with an href value equal to "#".

$("[href!='#']") select all elements with an href attribute NOT equal to "#".

$("[href$='.jpg']") select all elements with an href attribute that ends with ".jpg".

jQuery CSS selectors can be used to change CSS properties for HTML elements.

The following example changes the background-color of all p elements to yellow:

$("p").css("background-color","yellow");

Syntax	Description
$(this)	Current HTML element
$("p")	All <p> elements
$("p.intro")	All <p> elements with class="intro"
$(".intro")	All elements with class="intro"
$("#intro")	The first element with id="intro"
$("ul li:first")	The first <li> element of each <ul>
$("[href$='.jpg']")	All elements with an href attribute that ends with ".jpg"
$("div#intro .head")	All elements with class="head" inside a <div> element with id="intro"