How to solve cross domain problems

Cross domain concept ：

agreement 、 domain name 、 The same port is the same domain , Otherwise, it's all cross domain

Solving cross domain problems ：

1、 Use JSONP（json+padding） Fill in the data

2、CORS The way （ Cross-domain resource sharing ）, On the back end, you can configure cross domain

3、 Server agent , Access to third-party resources through server files