I. Main reasons for using Ajax
1. Better User experience through appropriate Ajax applications;
2. Transfer the previous server workload to the client, which facilitates the idle processing capability of the client to reduce the burden on the server and bandwidth, this saves ISP space and bandwidth rental costs.
Ii. ReferencesJesse James Garnett, the earliest author of the Ajax concept, believes that:
Ajax is short for Asynchronous JavaScript and XML.
Ajax is not a new language or technology. It is actually a combination of several technologies in a certain way to play their respective roles in the same collaboration, including
Use XHTML and CSS for standardized rendering;
Use DOM for Dynamic Display and interaction;
Use XML and XSLT for data exchange and processing;
Use XMLHttpRequest for asynchronous data reading;
Finally, use JavaScript to bind and process all data;
The working principle of Ajax is equivalent to adding an intermediate layer between the user and the server, so that user operations and server responses are asynchronous. Not all user requests are submitted to the server, for example, some data verification and data processing are handed over to the Ajax engine, the Ajax engine submits requests to the server only when it is determined that new data needs to be read from the server.
Figure 2-1
Figure 2-2