跨域问题 has been blocked by CORS policy: No ‘Access-Control-Allow-Origin‘ header is

错误信息

has been blocked by CORS policy: No 'Access-Control-Allow-Origin'
 header is present on the requested resource.

意思是：cors阻止了你请求的资源（跨域问题）；

解决方法:

spring项目在相应方法上加上这个注解

@CrossOrigin

这样这个错误就解决了。希望可以有所帮助！