HTTP状态的Php脚本[关闭]

I need your help for a PHP script. How do I respond with an appropriate HTTP status: 2xx for success, 4xx for bad request (no retry), or 5xx server unavailable (retry) from a specified url?

With http_response_code:

<?php
http_response_code(404);
?>

Send the header before any output is sent:

below PHP 5.4

header("HTTP/1.0 404 Not Found");    
header("HTTP/1.1 200 OK");    
header("HTTP/1.1 500 Internal Server Error");

PHP 5.4 and above

http_response_code(404);
http_response_code(200);
http_response_code(500);

More about sending HTTP headers with PHP: http://php.net/manual/en/function.header.php

An overview of the available header response codes: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html