如何解决php获取不到form数据

; Whether PHP will read the POST data.
; This option is enabled by default.
; Most likely, you won't want to disable this option globally. It causes $_POST
; and $_FILES to always be empty; the only way you will be able to read the
; POST data will be through the php://input stream wrapper. This can be useful
; to proxy requests or to process the POST data in a memory efficient fashion.
; http://php.net/enable-post-data-reading
enable_post_data_reading = On    //大约656行，修改此条

$raw = file_get_contents('php://input');//获取非表单数据echo $raw;//输出结果
PS：post时前端请求头要设置为
headers: {    "Content-type": "application/json; charset=utf-8"}