javascript - When using vue-resource to call the interface, why can't the data returned by the interface be seen and the browser displays it as null?

Question

As the title says, use vue-resource to call the back-end api. The back-end returns the front-end data, as shown in the figure. The front-end parameters: The code back-end returns data, but it is displayed as null on the browser. I am curious why it is displayed like this. If I can return the data If it is changed to invisible to users, will it also improve the data...

淡淡烟草味 · Answer

You can see if you can see the response body when you open other web pages in Firefox

滿天的星座 · Answer

Since the response in the browser is null, it means there is no data. Where did you come to the conclusion that the backend has data. It is recommended to use tools such as postman to test the interface