When the front and back ends are separated, the background debugging method

The front-end page sends a request

1. Click Network after F12
2. 'Refresh' the page if you don't see anything
3. Click All, you can see all the corresponding content

4. Keyword introduction           

Status	Return status, you can confirm whether it is successful                        200 is a successful return,                  30# is also normal, the                 problem occurs when the return code is 40# 50#
Type	Loading data or object type There is js html in script, front is font, xhr is the core object of ajax, and it is also an ajax request; document is page

5. Click the interface where Type is xhr

6. You can see the response, then you can see the response data or error message