nginx解决跨域,Access to XMLHttpRequest at ‘xx‘ from origin ‘xx‘ has been blocked by CORS policy

第一步：

server
{
    listen 80;
    server_name xxx;
    index      ;
    root /www/xxx
    # 添加如下代码
    add_header Access-Control-Allow-Origin '*';
    add_header Access-Control-Allow-Methods 'POST,PUT,GET,DELETE';
    add_header Access-Control-Allow-Headers 'version, access-token, user-token, Accept, apiAuth, User-Agent, Keep-Alive, Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With';
   }

第二步：
重启nginx

若依旧跨域并类似以下报错：

Request header field xxx is not allowed by Access-Control-Allow-Headers in preflight response

那么请在"add_header Access-Control-Allow-Headers"中添加你请求头参数

例如：
你的请求头中含有，“token”,"xx_id"等，
那么最终配置就是

    listen 80;
    server_name xxx;
    index      ;
    root /www/xxx
    # 添加如下代码
    add_header Access-Control-Allow-Origin '*';
    add_header Access-Control-Allow-Methods 'POST,PUT,GET,DELETE';
    # 对比原来的多增加了"token"及"xx_id"
    add_header Access-Control-Allow-Headers 'token,xx_id,version, access-token, user-token, Accept, apiAuth, User-Agent, Keep-Alive, Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With';
   }

然后重启Nginx就OK啦~！！！