php - 取消设置我的php文件发送的当前http标头，并替换为自定义的

setting custom header in PHP is available with header(); function but i want to unset all the headers that being sent from my PHP file to the browser and write my own headers something like

unset(headers());    
$headers = array(
'Accept' => '',
'Content-Type' => '',
..etc
);