Proitfusion

Course information

Ajax: - Ajax is a set of web development techniques that uses various web technologies on the client-side to create asynchronous web applications. With Ajax, web applications can send and retrieve data from a server asynchronously without interfering with the display and behaviour of the existing page.

AJAX stands for Asynchronous JavaScript and XML. AJAX is a new technique for creating better, faster, and more interactive web applications with the help of XML, HTML, CSS, and Java Script.

• Ajax uses XHTML for content, CSS for presentation, along with Document Object Model and JavaScript for dynamic content display.
• Conventional web applications transmit information to and from the sever using synchronous requests. It means you fill out a form, hit submit, and get directed to a new page with new information from the server.
• With AJAX, when you hit submit, JavaScript will make a request to the server, interpret the results, and update the current screen. In the purest sense, the user would never know that anything was even transmitted to the server.
• XML is commonly used as the format for receiving server data, although any format, including plain text, can be used.
• AJAX is a web browser technology independent of web server software.
• A user can continue to use the application while the client program requests information from the server in the background.
• Intuitive and natural user interaction. Clicking is not required, mouse movement is a sufficient event trigger.
• Data-driven as opposed to page-driven.

Introduction of Ajax

• Request object Creation
• Requesting the data
• Asynchronous data transfer
• Using the readyState property
• Callback function
• Using inner HTML
• Sending the request
• Requesting the data
• Error handling with try/catch
• Understanding HTTP

Using Xml and Json in Ajax Applications

• Introduction to XML
• XML and the DOM
• ResponseText Usage
• Using responseXML
• JSON vs XML
• Basics of JSON
• Using JavaScript literals
• CSS with Ajax

Object-Oriented Javascript and Custom Ajax Objects

• New operator
• Object constructors
• Prototypes
• Custom Ajax objects
• Ajax and forms
• Encoding

Troubleshooting and Debugging Ajax

• on error event handler
• Debugging Ajax with Firebug
• Tools for navigating the DOM
• Firefox DOM Inspector
• IE DOM Inspector
• Mouseover DOM Inspector (MODI)
• List of Live HTTP Headers
• Explain HTTP Status Codes

Using Javascript Libraries and Creating A Widget

• JavaScript libraries/frameworks
• Three types of libraries/frameworks
• DOM extension
• Application conveniences
• Widgets
• Explain The Prototype JavaScript Framework
• Using Prototypes Ajax Objects
• Using an accordion widget to display an Ajax response

Working With Xml Feeds and Providing Feedback to the User

• Working with XML News Feeds
• RSS .9x
• RSS 2.0
• RSS 1.0
• Atom
• Using the Scriptaculous library for visual effects
• The yellow fade technique
• Drag and drop functionality