Ajax Notes (i)

The following is a personal understanding, please correct me in the wrong place.

Ajax basic use is mainly used to implement the Web page and the server asynchronous interaction, so that users do not feel or do not wait for the page to refresh.

The core technology of Ajax is the XMLHttpRequest object, which is a Javascripe object.

The techniques used by Ajax are:· HTML is used to build Web forms and determine which fields are used by other parts of the application.
                                  · JavaScript code is the core code for running Ajax applications, helping to improve communication with server applications.
                                  · DHTML or dynamic HTML, which is used to dynamically update forms. We will use Div, span, and other dynamic HTML elements to mark HTML.
                                 · The Document Object Model DOM is used (through JavaScript code) to handle HTML structures and (in some cases) the XML returned by the server

The creation of a XMLHttpRequest object differs depending on the browser.

With Web pages and the Javascripe method and generated XMLHttpRequest objects to invoke, the basic process in an AJAX application is:

1, from the Web form to obtain the required data document.getElementById ("").
2, establish the URL to connect.
3, open the connection to the server Xmlhttprequest.open ().
4, set the server to run after completion of the function Xmlhttprequest.onreadystatechange.
5, send request Xmlhttprequest.send ().