php终极解决跨域问题

header('content-type:application:json;charset=utf8');
header('Access-Control-Allow-Origin:*');
header('Access-Control-Allow-Methods:POST');
header('Access-Control-Allow-Headers:x-requested-with,content-type');
header('Access-Control-Allow-Credentials: true'); // 设置是否允许发送 cookies
header('Content-Type: image/png');