跨域错误提示：

XMLHttpRequest cannot load http://xxx.com. Request header field Content-Type is not allowed by Access-Control-Allow-Headers.

解决方案：

php服务端程序设置头：

header('Access-Control-Allow-Origin: *');
header("Access-Control-Allow-Headers: Origin, X-Requested-With, Content-Type, Accept, x-file-name");
header('Access-Control-Allow-Methods: GET, POST, PUT,DELETE');

其实主要是看console返回的错误信息，适当修改以上代码的参数。哪个被拒绝了，就添加哪一个。