php网络状态代码判定

<?php
function HTTPStatus($num) {
    $http = array(
        100 => 'HTTP/1.1 100 Continue',
        101 => 'HTTP/1.1 101 Switching Protocols',
        200 => 'HTTP/1.1 200 OK',
        201 => 'HTTP/1.1 201 Created',
        202 => 'HTTP/1.1 202 Accepted',
        203 => 'HTTP/1.1 203 Non-Authoritative Information',
        204 => 'HTTP/1.1 204 No Content',
        205 => 'HTTP/1.1 205 Reset Content',
        206 => 'HTTP/1.1 206 Partial Content',
        300 => 'HTTP/1.1 300 Multiple Choices',
        301 => 'HTTP/1.1 301 Moved Permanently',
        302 => 'HTTP/1.1 302 Found',
        303 => 'HTTP/1.1 303 See Other',
        304 => 'HTTP/1.1 304 Not Modified',
        305 => 'HTTP/1.1 305 Use Proxy',
        307 => 'HTTP/1.1 307 Temporary Redirect',
        400 => 'HTTP/1.1 400 Bad Request',
        401 => 'HTTP/1.1 401 Unauthorized',
        402 => 'HTTP/1.1 402 Payment Required',
        403 => 'HTTP/1.1 403 Forbidden',
        404 => 'HTTP/1.1 404 Not Found',
        405 => 'HTTP/1.1 405 Method Not Allowed',
        406 => 'HTTP/1.1 406 Not Acceptable',
        407 => 'HTTP/1.1 407 Proxy Authentication Required',
        408 => 'HTTP/1.1 408 Request Time-out',
        409 => 'HTTP/1.1 409 Conflict',
        410 => 'HTTP/1.1 410 Gone',
        411 => 'HTTP/1.1 411 Length Required',
        412 => 'HTTP/1.1 412 Precondition Failed',
        413 => 'HTTP/1.1 413 Request Entity Too Large',
        414 => 'HTTP/1.1 414 Request-URI Too Large',
        415 => 'HTTP/1.1 415 Unsupported Media Type',
        416 => 'HTTP/1.1 416 Requested Range Not Satisfiable',
        417 => 'HTTP/1.1 417 Expectation Failed',
        500 => 'HTTP/1.1 500 Internal Server Error',
        501 => 'HTTP/1.1 501 Not Implemented',
        502 => 'HTTP/1.1 502 Bad Gateway',
        503 => 'HTTP/1.1 503 Service Unavailable',
        504 => 'HTTP/1.1 504 Gateway Time-out',
        505 => 'HTTP/1.1 505 HTTP Version Not Supported',
    );
 
    header($http[$num]);
 
    return
        array(
            'code' => $num,
            'error' => $http[$num],
        );
}