Richard York - Web Development with jQuery

Web Development with jQuery

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RICHARD YORK has written four previous Wrox books, including Beginning JavaScript and CSS Development with jQuery (2009).

PETER HENDRICKSON has been developing software as a hobby since 1989 and professionally since 2001. He is currently a Manager of Software Engineering at salesforce.com, where he has developed both user interface and middle-tier components for the Salesforce Marketing Cloud. In addition to his work technical editing many chapters of the book, Peter contributed by writing several chapters.

NIK DEVEREAUX joined ViaSat in 2003 and is currently a program director for ViaSat's Central Engineering department. He manages the Software Engineering Office and University Partnerships & Recruiting programs. In this role, Nik's primary goal is to grow the size, skill set, and strategic alignment of the entire software engineering community across all business areas and office locations. He received his bachelor's and master's degrees from UC San Diego.

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JQUERY HAS BECOME ESSENTIAL in the world of web development. jQuery's mission as a JavaScript library is simple: It strives to make the lives of web developers easier by making many tasks much easier. jQuery began as a library to patch cross-browser inconsistencies, to make developing in JavaScript easier, while it still provides a lot of cross-browser normalization. As browsers have advanced and filled in holes in compatibility, jQuery has become leaner, more efficient, and better at fulfilling the task of providing an API that makes developing JavaScript easier.

jQuery has the proven capability to reduce many lines of ordinary JavaScript to just a few lines, and, in many cases, just a single line of jQuery-enabled JavaScript. The trade-off is including the additional size and complexity of the jQuery library (and possibly additional related downloads) in the materials your users need to obtain to use your website or application. This is less of a trade-off today as more and more people have access to high-speed Internet. High-speed internet, although still pathetic in the United States when compared to some other nations, has inched up in overall speed. So, the additional download isn't all that much when you consider the big picture.

jQuery strives to remove barriers in JavaScript development by removing redundancy wherever possible. jQuery 1.9 and earlier focus more on normalizing cross-browser JavaScript development in key areas where browsers would otherwise differ, such as Microsoft's Event API and the W3C Event API, and other, more remedial tasks such as getting the mouse cursor's position when an event has taken place. With the normalization efforts taking place in the browsers, jQuery 2.0 can shed a great deal of legacy baggage that focused on bridging things such as event compatibility between Internet Explorer and everyone else. Now, the latest version of Internet Explorer has the standard event API in strict standards rendering mode, so when you include the right Document Type Declaration, there is no need to bridge event support.

jQuery 1.9 should be used if you need to work with older versions of Internet Explorer, such as IE8. Both jQuery 1.9 and jQuery 2.0 work with all the modern browsers, including the latest versions of Safari, Firefox, Google Chrome, and Internet Explorer.