xhr.open请求报跨域

Question

用浏览器直接访问文件地址，可以展示；
用Postman get请求仍然是正常的，但：
xhr.open('GET', url, true)就报错：
Access to XMLHttpRequest at http://100.2...xxx.jpg from origin 'http://localhost:8080' has been blocked by CORS policy: The 'Access-Control-Allow-Origin' header contains multiple values ', ', but only one is allowed.

Answer 1

建议了解下浏览器的同源策略。
https://www.baidu.com/s?ie=ut...