The spectator server data request failed. What are the five steps for Ajax get request to request data from the server?

As follows:

① Create ajax object

② Create httprequest

③Send httprequest

④Set ajax Callback function for object state changes

⑤ Determine whether the ajax status is equal to 4, do the corresponding business logic

The above introduces the five steps of the Ajax get request to request data from the server when the spectator server data request fails? , including content on failure of data request to the viewing server. I hope it will be helpful to friends who are interested in PHP tutorials.