AJAX allows for asynchronous JavaScript communication with web servers to update parts of a web page without reloading the entire page. It uses the XMLHttpRequest object to make HTTP requests from JavaScript, exchanging data with the server in the background without interfering with the display and behavior of the existing page. This improves interactivity, speed, and usability compared to traditional page reloading.
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What You Should Already Know: Ajax Asynchronous Javascript and XML
AJAX allows for asynchronous JavaScript communication with web servers to update parts of a web page without reloading the entire page. It uses the XMLHttpRequest object to make HTTP requests from JavaScript, exchanging data with the server in the background without interfering with the display and behavior of the existing page. This improves interactivity, speed, and usability compared to traditional page reloading.
AJAX allows for asynchronous JavaScript communication with web servers to update parts of a web page without reloading the entire page. It uses the XMLHttpRequest object to make HTTP requests from JavaScript, exchanging data with the server in the background without interfering with the display and behavior of the existing page. This improves interactivity, speed, and usability compared to traditional page reloading.
Copyright:
Attribution Non-Commercial (BY-NC)
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Download as PDF, TXT or read online from Scribd
Download as pdf or txt
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What You Should Already Know: Ajax Asynchronous Javascript and XML
AJAX allows for asynchronous JavaScript communication with web servers to update parts of a web page without reloading the entire page. It uses the XMLHttpRequest object to make HTTP requests from JavaScript, exchanging data with the server in the background without interfering with the display and behavior of the existing page. This improves interactivity, speed, and usability compared to traditional page reloading.
Copyright:
Attribution Non-Commercial (BY-NC)
Available Formats
Download as PDF, TXT or read online from Scribd
Download as pdf or txt
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AJAX
What You Should Already Know
Before you continue you should have a basic understanding of the following: HTML / XHTML JavaScript
AJAX = Asynchronous JavaScript and XML
AJAX is not a new programming language, but a technique for creating better, faster, and more interactive web applications. With AJAX, your JavaScript can communicate directly with the server, using the JavaScript XMLHttpRequest object. With this object, your JavaScript can trade data with a web server, without reloading the page AJAX uses asynchronous data transfer (HTTP requests) between the browser and the web server, allowing web pages to request small bits of information from the server instead of whole pages. The AJAX technique makes Internet applications smaller, faster and more user-friendly. AJAX is a browser technology independent of web server software. AJAX is Based on Web Standards AJAX is based on the following web standards, and these standards are well defined, and supported by all major browsers. AJAX applications are browser/platform independent. JavaScript XML HTML CSS
AJAX is About Better Internet Applications
Web applications have many benefits over desktop applications; they can reach a larger audience, they are easier to install and support, and easier to develop. However, Internet applications are not always as "rich" and user-friendly as traditional desktop applications. With AJAX, Internet applications can be made richer and more user-friendly. There is nothing new to learn. AJAX is based on existing standards. These standards have been used by most developers for several years. AJAX Uses HTTP Requests In traditional JavaScript coding, if you want to get any information from a database or a file on the server, or send user information to a server, you will have to make an HTML form and GET or POST data to the server. The user will have to click the "Submit" button to send/get the information, wait for the server to respond, then a new page will load with the results. Because the server returns a new page each time the user submits input, traditional web applications can run slowly and tend to be less user-friendly. With AJAX, your JavaScript communicates directly with the server, through the JavaScript XMLHttpRequest object With an HTTP request, a web page can make a request to, and get a response from a web server - without reloading the page. The user will stay on the same page, and he or she will not notice that scripts request pages, or send data to a server in the background. The XMLHttpRequest Object By using the XMLHttpRequest object, a web developer can update a page with data from the server after the page has loaded! AJAX was made popular in 2005 by Google (with Google Suggest). Google Suggest is using the XMLHttpRequest object to create a very dynamic web interface: When you start typing in Google's search box, a JavaScript sends the letters off to a server and the server returns a list of suggestions. The XMLHttpRequest object is supported in Internet Explorer 5.0+, Safari 1.2, Mozilla 1.0 / Firefox, Opera 8+, and Netscape 7.
AJAX - Browser Support
The keystone of AJAX is the XMLHttpRequest object. Did you notice something
missing from the HTML form? AJAX - More About the XMLHttpRequest Object
Before sending data to the server, we have to explain three
important properties of the XMLHttpRequest object. 1. The onreadystatechange Property After a request to the server, we need a function that can receive the data that is returned by the server. The onreadystatechange property stores your function that will process the response from a server. This is not a method, the function is stored in the property to be called automatically. The following code sets the onreadystatechange property and stores an empty function inside it: xmlHttp. > { // We are going to write some code here } 2. The readyState Property 3. The responseText Property AJAX - Sending a Request to the Server
4.1 Write HTML Code That Displays Three Hyperlinks To Different Websites. The Websites Should Open in A New Window When The User Clicks On The Hyperlinks