JavaScript Ajax-1 Ajax (Ajax principles, Ajax object properties and methods)

First, the principle of Ajax

Introduction to Ajax

-Asynchronous JavaScript and XML asynchronous JavaScript and XML

-Ajax is a technique used to improve the user experience, essentially by using the XMLHttpRequest object to send requests asynchronously to the server

-The server returns part of the data instead of a full page, changing the local content in the page without refreshing the page

How Ajax Works

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Get Ajax objects

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Second, Ajax object properties and methods

Properties and methods for asynchronous objects

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onReadyStateChange

-onReadyStateChange: Binds an event handler function to handle the ReadyStateChange event

-Note: When the value of the readystate of an Ajax object changes, for example, from 0 to 1, a ReadyStateChange event is generated

ReadyState

-ReadyState: A total of 5 values, respectively, are 0,1,2,3,4, respectively, representing the status of the Ajax object and the server communication

-for example, a value of 4 o'clock indicates that the Ajax object has obtained all the data returned by the server

Summary: This chapter focuses on Ajax (Ajax principles, Ajax object properties and methods)

This article from the "Flying Ants" blog, declined to reprint!

JavaScript Ajax-1 Ajax (Ajax principles, Ajax object properties and methods)