Book Image

Learning jQuery - Fourth Edition - Fourth Edition

Book Image

Learning jQuery - Fourth Edition - Fourth Edition

Overview of this book

To build interesting, interactive sites, developers are turning to JavaScript libraries such as jQuery to automate common tasks and simplify complicated ones. Because many web developers have more experience with HTML and CSS than with JavaScript, the library's design lends itself to a quick start for designers with little programming experience. Experienced programmers will also be aided by its conceptual consistency. LearningjQuery - Fourth Edition is revised and updated version of jQuery. You will learn the basics of jQuery for adding interactions and animations to your pages. Even if previous attempts at writing JavaScript have left you baffled, this book will guide you past the pitfalls associated with AJAX, events, effects, and advanced JavaScript language features. Starting with an introduction to jQuery, you will first be shown how to write a functioning jQuery program in just three lines of code. Learn how to add impact to your actions through a set of simple visual effects and to create, copy, reassemble, and embellish content using jQuery's DOM modification methods. The book will take you through many detailed, real-world examples, and even equip you to extend the jQuery library itself with your own plug-ins.
Table of Contents (24 chapters)
Learning jQuery Fourth Edition
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Selector expressions


The jQuery factory function $() is used to find elements on the page to work with. This function takes a string composed of CSS-like syntax, called a selector expression. Selector expressions are discussed in detail in Chapter 2, Selecting Elements.

Simple CSS

Selector

Matches

*

All elements.

#id

The element with the given ID.

element

All elements of the given type.

.class

All elements with the given class.

a, b

Elements that are matched by a or b.

a b

Elements b that are descendants of a.

a > b

Elements b that are children of a.

a + b

Elements b that immediately follow a.

a ~ b

Elements b that are siblings of a and follow a.

Position among siblings

Selector

Matches

:nth-child(index)

Elements that are the index child of their parent element (1-based).

:nth-child(even)

Elements that are an even child of their parent element (1-based).

:nth-child(odd)

Elements which are an odd child of their parent element (1-based).

:nth-child(formula)

Elements that are the nth child of their parent element (1-based). Formulas are of the form an+b for integers a and b.

:nth-last-child()

The same as :nth-child(), but counting from the last element to the first.

:first-child

Elements that are the first child of their parent.

:last-child

Elements that are the last child of their parent.

:only-child

Elements that are the only child of their parent.

:nth-of-type()

The same as :nth-child(), but only counting elements of the same element name.

:nth-last-of-type()

The same as :nth-last-child(), but only counting elements of the same element name.

:first-of-type

Elements which are the first child of the same element name among their siblings.

:last-of-type

Elements that are the last child of the same element name among their siblings.

:only-of-type()

Elements that are the only child of the same element name among their siblings.

Position among matched elements

Selector

Matches

:first

The first element in the result set.

:last

The last element in the result set.

:not(a)

All elements in the result set that are not matched by a.

:even

Even elements in the result set (0-based).

:odd

Odd elements in the result set (0-based).

:eq(index)

A numbered element in the result set (0-based).

:gt(index)

All elements in the result set after (greater than) the given index (0-based).

:lt(index)

All elements in the result set before (less than) the given index (0-based).

Attributes

Selector

Matches

[attr]

Elements that have the attribute attr.

[attr="value"]

Elements whose attr attribute is value.

[attr!="value"]

Elements whose attr attribute is not value.

[attr^="value"]

Elements whose attr attribute begins with value.

[attr$="value"]

Elements whose attr attribute ends with value.

[attr*="value"]

Elements whose attr attribute contains the substring value.

[attr~="value"]

Elements whose attr attribute is a space-delimited set of strings, one of which is value.

[attr|="value"]

Elements whose attr attributes is either equal to value or begins with value followed by a hyphen.

Forms

Selector

Matches

:input

All <input>, <select>, <textarea>, and <button> elements.

:text

The <input> elements with type="text".

:password

The <input> elements with type="password".

:file

The <input> elements with type="file".

:radio

The <input> elements with type="radio".

:checkbox

The <input> elements with type="checkbox".

:submit

The <input> elements with type="submit".

:image

The <input> elements with type="image".

:reset

The <input> elements with type="reset".

:button

The <input> elements with type="button" and <button> elements.

:enabled

Enabled form elements.

:disabled

Disabled form elements.

:checked

Checked checkboxes and radio buttons.

:selected

Selected <option> elements.

Miscellaneous selectors

Selector

Matches

:root

The root element of the document.

:header

Header elements (for example, <h1>, <h2>).

:animated

Elements with an animation in progress.

:contains(text)

Elements containing the given text.

:empty

Elements with no child nodes.

:has(a)

Elements containing a descendant element matching a.

:parent

Elements that have child nodes.

:hidden

Elements that are hidden, either through CSS or because they are <input type="hidden" />.

:visible

The inverse of :hidden.

:focus

The element that has the keyboard focus.

:lang(language)

Elements with the given language code (either due to a lang attribute on the element or an ancestor, or a <meta> declaration).

:target

Whichever element is targeted by the URI's fragment identifier, if any.