Jeremy McPeak Knihy

S nedávnými pokroky v oblasti JavaScriptu mohou vývojáři dosahovat nevídaných uživatelských prožitků ve webových aplikacích. Tradiční architektura "klikni-a-čekej" byla překonána díky Ajaxu, který umožňuje funkce dříve dostupné pouze v desktopových aplikacích. Kniha se zaměřuje na různé aspekty Ajaxu, včetně vytváření HTTP požadavků a přenosu dat zpět ke klientovi. Ovládnete techniky Ajaxu a vzory komunikace klient-server, které se dnes běžně používají. V šestnácti kapitolách se naučíte základy Ajaxu, ajaxové vzory a knihovny, spravování ajaxových požadavků a technologie jako XML, XPath, XSLT, RSS/Atom, JSON a COMET. Dále se seznámíte s API pro mapy a nástroji pro ladění Ajaxu a budete schopni vytvářet widgety pro webové stránky. Kniha končí dvěma případovými studiemi, které ilustrují praktické použití Ajaxu při vytváření čtečky zdrojů RSS a webové e-mailové aplikace. Tímto způsobem získáte ucelený přehled o možnostech a aplikacích Ajaxu v moderním webovém vývoji.

Written for experienced web developers, this guide demonstrates how to integrate CSS, XML, and JavaScript into Ajax, enabling the creation of sophisticated and responsive user interfaces that move beyond the traditional "click-and-wait" model. It covers various request brokers, including hidden frames, iframes, and XMLHttp, detailing when to use each. Readers will explore different Ajax techniques and patterns for effective client-server communication in web applications. A case study illustrates the application of these techniques in developing an AjaxMail application. Additionally, the book features practical examples such as web widgets for news tickers, weather information, web search, preloading pages in online articles, incremental form validation using Google Web APIs, and creating an autosuggest text box. Familiarity with CSS, XML, JavaScript, and HTML is essential for readers to fully engage with the content, which also delves into Ajax patterns, XPath and XSLT support in browsers, syndication, web services, JSON, and various Ajax frameworks like JPSpan, DWR, and Ajax.NET. By the end, readers will possess the knowledge to implement their own Ajax solutions effectively.

JavaScript is a scripting language that enables you to enhance static web applications by providing dynamic, personalized, and interactive content. This improves the experience of visitors to your site and makes it more likely that they will visit again. You must have seen the flashy drop-down menus, moving text, and changing content that are now widespread on web sites—they are enabled through JavaScript. Supported by all the major browsers, JavaScript is the language of choice on the Web. It can even be used outside web applications—to automate administrative tasks, for example. This book aims to teach you all you need to know to start experimenting with what it is, how it works, and what you can do with it. Starting from the basic syntax, you'll move on to learn how to create powerful web applications. Don't worry if you've never programmed before—this book will teach you all you need to know, step by step. You'll find that JavaScript can be a great introduction to the world of with the knowledge and understanding that you'll gain from this book, you'll be able to move on to learn newer and more advanced technologies in the world of computing. In order to get the most out of this book, you'll need to have an understanding of HTML and how to create a static web page. You don't need to have any programming experience. This book will also suit you if you have some programming experience already, and would like to turn your hand to web programming. You will know a fair amount about computing concepts, but maybe not as much about web technologies. Alternatively, you may have a design background and know relatively little about the Web and computing concepts. For you, JavaScript will be a cheap and relatively easy introduction to the world of programming and web application development. Whoever you are, we hope that this book lives up to your expectations. You'll begin by looking at exactly what JavaScript is, and taking your first steps with the underlying language and syntax. You'll learn all the fundamental programming concepts, including data and data types, and structuring your code to make decisions in your programs or to loop over the same piece of code many times. Once you're comfortable with the basics, you'll move on to one of the key ideas in JavaScript—the object. You'll learn how to take advantage of the objects that are native to the JavaScript language, such as dates and strings, and find out how these objects enable you to manage complex data and simplify your programs. Next, you'll see how you can use JavaScript to manipulate objects made available to you in the browser, such as forms, windows, and other controls. Using this knowledge, you can start to create truly professional-looking applications that enable you to interact with the user. Long pieces of code are very hard to get right every time—even for the experienced programmer—and JavaScript code is no exception. You look at common syntax and logical errors, how you can spot them, and how to use the Microsoft Script Debugger to aid you with this task. Also, you need to examine how to handle the errors that slip through the net, and ensure that these do not detract from the experience of the end user of your application. From here, you'll move on to more advanced topics, such as using cookies and jazzing up your web pages with dynamic HTML and XML. Finally, you'll be looking at a relatively new and exciting technology, remote scripting. This allows your JavaScript in a HTML page to communicate directly with a server, and useful for, say, looking up information on a database sitting on your server. If you have the Google toolbar you'll have seen something like this in action already. When you type a search word in the Google toolbar, it comes up with suggestions, which it gets via the Google search database. All the new concepts introduced in this book will be illustrated with practical examples, which enable you to experiment with JavaScript and build on the theory that you have just learned. The appendix provides solutions to the exercises included at the end of most chapters throughout the book. During the first half of the book, you'll also be building up a more complex sample application—an online trivia quiz—which will show you how JavaScript is used in action in a real-world situation.

Ajax es un término que engloba todo lo que rodea el uso de peticiones HTTP asincrónicas iniciadas por JavaScript con el propósito de recuperar información del servidor sin descargar la página. Proporciona a los desarrolladores la capacidad de crear interfaces de usuario más sofisticadas y con mejor respuesta, rompiendo así con el paradigma de " hacer clic y esperar " que hasta ahora había dominado la Web desde su creación. En este libro, se estudian los distintos agentes de peticiones y explica cuándo debe utilizarse cada uno. Se desarrollan diferentes técnicas y patrones de Ajax para ejecutar procesos de comunicación cliente-servidor en su sitio y en sus aplicaciones web, así como una variedad de patrones de diseño Ajax para utilizar en circunstancias específicas de recuperación de datos. Cada capítulo se basa en la información de los capítulos anteriores, de forma que al final del libro habrá adquirido los conocimientos prácticos necesarios para implementar sus propias soluciones Ajax. Este libro está dirigido a desarrolladores web que quieran mejorar la funcionalidad de sus sitios y aplicaciones. Es necesario estar familiarizado con JavaScript, HTML y CSS, así como tener experiencia con un lenguaje del lado del servidor tal como PHP o .NET.