jQuery 发送 ajax 跨域请求，java 后端配置允许跨域

 Java代码的话，在返回响应之前调用如下代码中的allowCrossDomainAccess()方法：

/**
 * 允许跨域访问
 */
public void allowCrossDomainAccess(HttpServletResponse response){
    response.setHeader("Access-Control-Allow-Origin", "*");
    response.setHeader("Access-Control-Allow-Methods", "*");
    response.setHeader("Access-Control-Allow-Headers:x-requested-with", "Authorization,Origin,X-Requested-With,Content-Type,Accept,content-Type,origin,x-requested-with,content-type,accept,authorization,token,id,X-Custom-Header,X-Cookie,Connection,User-Agent,Cookie");
} 

参考：

https://blog.csdn.net/ldx891113/article/details/50887776

https://blog.csdn.net/fdipzone/article/details/46390573

https://blog.csdn.net/moxiaoya1314/article/details/80430300

全文完

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