Ajax stands for "A
synchronous
Javascript
And
X
ML
" (asynchronous JavaScript and XML), which refers to
a
web development technology for creating interactive web applications.
Ajax is a technique for creating fast and dynamic web pages.
Ajax enables web pages to be updated asynchronously by exchanging small amounts of data with the server in the background. This means that parts of a page can be updated without reloading the entire page.
Traditional web pages (without using Ajax) must reload the entire web page if the content needs to be updated.
Ajax is not a new programming language, but a technology for creating better, faster, and more interactive web applications.
Use JavaScript to make requests to servers and process responses without blocking the user! The core object
XMLHTTPRequest
. Through this object, your JavaScript can exchange data with the web server without reloading the page, that is, a partial refresh effect can be produced without needing to refresh the page.
Ajax uses asynchronous data transfer (HTTP requests) between the browser and the web server, which allows web pages to request small amounts of information from the server instead of the entire page.
Ajax is a browser technology independent of Web server software. Ajax is based on the following web standards:
The Web standards used in Ajax by JavaScript, XML,
HTML
and
CSS
are well defined and supported by all major browsers. Ajax applications are browser and platform independent.
Web applications have many advantages over desktop applications; they can reach a wide range of users, they are easier to install and maintain, and they are easier to develop.
However, Internet applications are not as complete and friendly as traditional desktop applications. With Ajax, Internet applications can become more sophisticated and friendly.
Development mode:
many
Important technical and Ajax development patterns can be derived from existing knowledge. For example, an application that sends requests to a server must include request order, priority, timeout responses, error handling, and callbacks, many of which are already included in Web services. At the same time, as the technology matures, there are still many areas that need to be improved, especially the ease of use of the UI part.
Ajax development is very different from traditional
B/S
development. These differences introduce new programming problems, the biggest being ease of use. Since Ajax relies on the browser's JavaScript and XML, browser compatibility and supported standards become as important as JavaScript's runtime performance. Most of these problems stem from the combination of browsers,
servers
, and technologies, so it is important to understand how to best use these technologies.
Combining various changing technologies and a strongly coupled client-server environment, Ajax proposes a new development method. Ajax developers must understand the traditional
MVC
architecture, which limits the boundaries between application layers. At the same time, developers also need to consider the outside of the B/S environment and use Ajax technology to reshape the MVC boundary. Most importantly, Ajax developers must forbid thinking of a Web application as a collection of pages and need to think of it as a single page. Once the scope between UI design and service architecture is strictly separated, developers need a collection of updated and changing technologies.