跨域问题解决
has been blocked by CORS policy: The value of the 'Access-Control-Allow-Origin' header in the response must not be the wildcard '*' when the request's credentials mode is 'include'. The credentials mode of requests initiated by the XMLHttpRequest is controlled by the withCredentials attribute
这个错误是由于同时设置了 Access-Control-Allow-Origin=* 和 Access-Control-Allow-Credentials=true
解决办法是把*改为指定地址