AJAX features

Sends an HTTP request to the server without refreshing the page and gets an HTTP response

Patients with a

Baidu keyword related list

Example 2

The registration page checks if the user name is usable

Example 3

Jingdong’s secondary classification

Secondary categories will not be requested or displayed without mouse over primary categories

Taobao classification module

Cases of four

Toutiao rolls to the bottom and automatically loads a new page, just like moments

Cases of five

The page showing different content under different modules is not refreshed

Cases of six

An image rendering web version of the tool

Each time an image is drawn or the position of an image is changed, a request is made to the server but the page is not refreshed

The advantages and disadvantages

Resolve cross-domain problems

Setting the cross-domain file response header in server.js ensures that any page cross-domain request will work, right