Ajax

Başlarken
Ajax'a giriş.

Asenkronize JavaScript + XML, aslında bir teknoloji değil, 2005 yılında Jesse James tarafından geliştirilmiştir. AJAX, HTML , XHTML , Cascading Style Sheets, JavaScript, The Document Object Model, XML, XSLT ve en önemlisi XMLHttpRequest object gibi mevcut birçok teknolojinin bir arada kullanılmasıyla tanımlanır.

Web uygulamaları Ajax modelinde bu teknolojilerle birleştirildiğinde, tarayıcının sayfayı yeniden yükleme olmadan kullanıcı arayüzü hızlı, eklenmiş güncelleştirmeler yapmak mümkün. Böylece uygulama daha hızlı ve daha iyi olarak kullanıcı eylemlerine yanıt verir.

Although X in Ajax stands for XML, JSON is used more than XML nowadays because of its many advantages such as being lighter and a part of JavaScript. Both JSON and XML are used for packaging information in Ajax model.

Documentation

Getting Started

This article guides you through the Ajax basics and gives you two simple hands-on examples to get you started.

Using the XMLHttpRequest API

The XMLHttpRequest API is the core of Ajax. This article will explain you how to use some Ajax techniques, like:

analyzing and manipulating the response of the server
monitoring the progress of a request
submitting forms and upload binary files – in pure Ajax, or using FormData objects
creating synchronous or asynchronous requests
using Ajax within Web workers

Server-sent events

Traditionally, a web page has to send a request to the server to receive new data; that is, the page requests data from the server. With server-sent events, it's possible for a server to send new data to a web page at any time, by pushing messages to the web page. These incoming messages can be treated as Events + data inside the web page. See also: Using server-sent events.

Pure-Ajax navigation example

This article provides a working (minimalist) example of a pure-Ajax web site composed only of three pages.

Sending and Receiving Binary Data

The responseType property of the XMLHttpRequest object can be set to change the expected response type from the server. Possible values are the empty string (default), "arraybuffer", "blob", "document", "json", and "text". The response property will contain the entity body according to responseType, as an ArrayBuffer, Blob, Document, JSON, or string. This article will show some Ajax I/O techniques.

XML

The Extensible Markup Language (XML) is a W3C-recommended general-purpose markup language for creating special-purpose markup languages. It is a simplified subset of SGML, capable of describing many different kinds of data. Its primary purpose is to facilitate the sharing of data across different systems, particularly systems connected via the Internet.

JXON

JXON stands for lossless Javascript XML Object Notation, it is a generic name by which is defined the representation of Javascript object trees (JSON) using XML.

Parsing and serializing XML

How to parse an XML document from a string, a file or via javascript and how to serialize XML documents to strings, Javascript Object trees (JXON) or files.

XPath

XPath stands for XML Path Language, it uses a non-XML syntax that provides a flexible way of addressing (pointing to) different parts of an XML document. As well as this, it can also be used to test addressed nodes within a document to determine whether they match a pattern or not.

The FileReader API

The FileReader API lets web applications asynchronously read the contents of files (or raw data buffers) stored on the user's computer, using File or Blob objects to specify the file or data to read. File objects may be obtained from a FileList object returned as a result of a user selecting files using the <input> element, from a drag and drop operation's DataTransfer object, or from the mozGetAsFile() API on an HTMLCanvasElement.

HTML in XMLHttpRequest

The W3C XMLHttpRequest specification adds HTML parsing support to XMLHttpRequest, which originally supported only XML parsing. This feature allows Web apps to obtain an HTML resource as a parsed DOM using XMLHttpRequest.

Other resources