Header php ошибка сервера

This is a short guide on how to send a 500 Internal Server Error header to the client using PHP. This is useful because it allows us to tell the client that the server has encountered an unexpected condition and that it cannot fulfill the request.

Below, I have created a custom PHP function called internal_error.

When the PHP function above is called, the script’s execution is halted and “Something went wrong!” is printed out onto the page.

Furthermore, if you inspect the HTTP headers with your browser’s developer console, you will see that the function is returning a 500 Internal Server Error status code:

Google’s Developer Tools showing the 500 Internal Server Error status that was returned.

To send the 500 status code, we used PHP’s header function like so:

Note that we used the SERVER_PROTOCOL variable in this case because the client might be using HTTP 1.0 instead of HTTP 1.1. In other examples, you will find developers making the assumption that the client will always be using HTTP 1.1.

This is not the case.

The problem with PHP is that it doesn’t always send a 500 Internal Server Error when an exception is thrown or a fatal error occurs.

This can cause a number of issues:

1. It becomes more difficult to handle failed Ajax calls, as the server in question is still responding with a 200 OK status. For example: The JQuery Ajax error handling functions will not be called.
2. Search engines such as Google may index your error pages. If this happens, your website may lose its rankings.
3. Other HTTP clients might think that everything is A-OK when it is not.

Note that if you are using PHP version 5.4 or above, you can use the http_response_code function:

Источник

http_response_code

(PHP 5 >= 5.4.0, PHP 7, PHP

http_response_code — Get or Set the HTTP response code

Description

Gets or sets the HTTP response status code.

Parameters

The optional response_code will set the response code.

Return Values

If response_code is provided, then the previous status code will be returned. If response_code is not provided, then the current status code will be returned. Both of these values will default to a 200 status code if used in a web server environment.

false will be returned if response_code is not provided and it is not invoked in a web server environment (such as from a CLI application). true will be returned if response_code is provided and it is not invoked in a web server environment (but only when no previous response status has been set).

Examples

Example #1 Using http_response_code() in a web server environment

// Get the current response code and set a new one
var_dump ( http_response_code ( 404 ));

// Get the new response code
var_dump ( http_response_code ());
?>

The above example will output:

Example #2 Using http_response_code() in a CLI environment

// Get the current default response code
var_dump ( http_response_code ());

// Set a response code
var_dump ( http_response_code ( 201 ));

// Get the new response code
var_dump ( http_response_code ());
?>

The above example will output:

See Also

• header() — Send a raw HTTP header
• headers_list() — Returns a list of response headers sent (or ready to send)

User Contributed Notes 18 notes

If your version of PHP does not include this function:

if (! function_exists ( ‘http_response_code’ )) <
function http_response_code ( $code = NULL ) <

switch ( $code ) <
case 100 : $text = ‘Continue’ ; break;
case 101 : $text = ‘Switching Protocols’ ; break;
case 200 : $text = ‘OK’ ; break;
case 201 : $text = ‘Created’ ; break;
case 202 : $text = ‘Accepted’ ; break;
case 203 : $text = ‘Non-Authoritative Information’ ; break;
case 204 : $text = ‘No Content’ ; break;
case 205 : $text = ‘Reset Content’ ; break;
case 206 : $text = ‘Partial Content’ ; break;
case 300 : $text = ‘Multiple Choices’ ; break;
case 301 : $text = ‘Moved Permanently’ ; break;
case 302 : $text = ‘Moved Temporarily’ ; break;
case 303 : $text = ‘See Other’ ; break;
case 304 : $text = ‘Not Modified’ ; break;
case 305 : $text = ‘Use Proxy’ ; break;
case 400 : $text = ‘Bad Request’ ; break;
case 401 : $text = ‘Unauthorized’ ; break;
case 402 : $text = ‘Payment Required’ ; break;
case 403 : $text = ‘Forbidden’ ; break;
case 404 : $text = ‘Not Found’ ; break;
case 405 : $text = ‘Method Not Allowed’ ; break;
case 406 : $text = ‘Not Acceptable’ ; break;
case 407 : $text = ‘Proxy Authentication Required’ ; break;
case 408 : $text = ‘Request Time-out’ ; break;
case 409 : $text = ‘Conflict’ ; break;
case 410 : $text = ‘Gone’ ; break;
case 411 : $text = ‘Length Required’ ; break;
case 412 : $text = ‘Precondition Failed’ ; break;
case 413 : $text = ‘Request Entity Too Large’ ; break;
case 414 : $text = ‘Request-URI Too Large’ ; break;
case 415 : $text = ‘Unsupported Media Type’ ; break;
case 500 : $text = ‘Internal Server Error’ ; break;
case 501 : $text = ‘Not Implemented’ ; break;
case 502 : $text = ‘Bad Gateway’ ; break;
case 503 : $text = ‘Service Unavailable’ ; break;
case 504 : $text = ‘Gateway Time-out’ ; break;
case 505 : $text = ‘HTTP Version not supported’ ; break;
default:
exit( ‘Unknown http status code «‘ . htmlentities ( $code ) . ‘»‘ );
break;
>

$protocol = (isset( $_SERVER [ ‘SERVER_PROTOCOL’ ]) ? $_SERVER [ ‘SERVER_PROTOCOL’ ] : ‘HTTP/1.0’ );

header ( $protocol . ‘ ‘ . $code . ‘ ‘ . $text );

$GLOBALS [ ‘http_response_code’ ] = $code ;

$code = (isset( $GLOBALS [ ‘http_response_code’ ]) ? $GLOBALS [ ‘http_response_code’ ] : 200 );

?>

In this example I am using $GLOBALS, but you can use whatever storage mechanism you like. I don’t think there is a way to return the current status code:

For reference the error codes I got from PHP’s source code:

And how the current http header is sent, with the variables it uses:

Note that you can NOT set arbitrary response codes with this function, only those that are known to PHP (or the SAPI PHP is running on).

The following codes currently work as expected (with PHP running as Apache module):
200 – 208, 226
300 – 305, 307, 308
400 – 417, 422 – 424, 426, 428 – 429, 431
500 – 508, 510 – 511

Codes 0, 100, 101, and 102 will be sent as «200 OK».

Everything else will result in «500 Internal Server Error».

If you want to send responses with a freestyle status line, you need to use the `header()` function:

( «HTTP/1.0 418 I’m A Teapot» ); ?>

When setting the response code to non-standard ones like 420, Apache outputs 500 Internal Server Error.

This happens when using header(0,0,420) and http_response_code(420).
Use header(‘HTTP/1.1 420 Enhance Your Calm’) instead.

Note that the response code in the string IS interpreted and used in the access log and output via http_response_code().

Status codes as an array:

= array( 100 => «Continue» , 101 => «Switching Protocols» , 102 => «Processing» , 200 => «OK» , 201 => «Created» , 202 => «Accepted» , 203 => «Non-Authoritative Information» , 204 => «No Content» , 205 => «Reset Content» , 206 => «Partial Content» , 207 => «Multi-Status» , 300 => «Multiple Choices» , 301 => «Moved Permanently» , 302 => «Found» , 303 => «See Other» , 304 => «Not Modified» , 305 => «Use Proxy» , 306 => «(Unused)» , 307 => «Temporary Redirect» , 308 => «Permanent Redirect» , 400 => «Bad Request» , 401 => «Unauthorized» , 402 => «Payment Required» , 403 => «Forbidden» , 404 => «Not Found» , 405 => «Method Not Allowed» , 406 => «Not Acceptable» , 407 => «Proxy Authentication Required» , 408 => «Request Timeout» , 409 => «Conflict» , 410 => «Gone» , 411 => «Length Required» , 412 => «Precondition Failed» , 413 => «Request Entity Too Large» , 414 => «Request-URI Too Long» , 415 => «Unsupported Media Type» , 416 => «Requested Range Not Satisfiable» , 417 => «Expectation Failed» , 418 => «I’m a teapot» , 419 => «Authentication Timeout» , 420 => «Enhance Your Calm» , 422 => «Unprocessable Entity» , 423 => «Locked» , 424 => «Failed Dependency» , 424 => «Method Failure» , 425 => «Unordered Collection» , 426 => «Upgrade Required» , 428 => «Precondition Required» , 429 => «Too Many Requests» , 431 => «Request Header Fields Too Large» , 444 => «No Response» , 449 => «Retry With» , 450 => «Blocked by Windows Parental Controls» , 451 => «Unavailable For Legal Reasons» , 494 => «Request Header Too Large» , 495 => «Cert Error» , 496 => «No Cert» , 497 => «HTTP to HTTPS» , 499 => «Client Closed Request» , 500 => «Internal Server Error» , 501 => «Not Implemented» , 502 => «Bad Gateway» , 503 => «Service Unavailable» , 504 => «Gateway Timeout» , 505 => «HTTP Version Not Supported» , 506 => «Variant Also Negotiates» , 507 => «Insufficient Storage» , 508 => «Loop Detected» , 509 => «Bandwidth Limit Exceeded» , 510 => «Not Extended» , 511 => «Network Authentication Required» , 598 => «Network read timeout error» , 599 => «Network connect timeout error» );
?>

Source: Wikipedia «List_of_HTTP_status_codes»

Do not mix the use of http_response_code() and manually setting the response code header because the actual HTTP status code being returned by the web server may not end up as expected. http_response_code() does not work if the response code has previously been set using the header() function. Example:

( ‘HTTP/1.1 401 Unauthorized’ );
http_response_code ( 403 );
print( http_response_code ());
?>

The raw HTTP response will be (notice the actual status code on the first line does not match the printed http_response_code in the body):

HTTP/1.1 401 Unauthorized
Date: Tue, 24 Nov 2020 13:49:08 GMT
Server: Apache
Connection: Upgrade, Keep-Alive
Keep-Alive: timeout=5, max=100
Transfer-Encoding: chunked
Content-Type: text/html; charset=UTF-8

I only tested it on Apache. I am not sure if this behavior is specific to Apache or common to all PHP distributions.

You can also create a enum by extending the SplEnum class.
/** HTTP status codes */
class HttpStatusCode extends SplEnum <
const __default = self :: OK ;

const SWITCHING_PROTOCOLS = 101 ;
const OK = 200 ;
const CREATED = 201 ;
const ACCEPTED = 202 ;
const NONAUTHORITATIVE_INFORMATION = 203 ;
const NO_CONTENT = 204 ;
const RESET_CONTENT = 205 ;
const PARTIAL_CONTENT = 206 ;
const MULTIPLE_CHOICES = 300 ;
const MOVED_PERMANENTLY = 301 ;
const MOVED_TEMPORARILY = 302 ;
const SEE_OTHER = 303 ;
const NOT_MODIFIED = 304 ;
const USE_PROXY = 305 ;
const BAD_REQUEST = 400 ;
const UNAUTHORIZED = 401 ;
const PAYMENT_REQUIRED = 402 ;
const FORBIDDEN = 403 ;
const NOT_FOUND = 404 ;
const METHOD_NOT_ALLOWED = 405 ;
const NOT_ACCEPTABLE = 406 ;
const PROXY_AUTHENTICATION_REQUIRED = 407 ;
const REQUEST_TIMEOUT = 408 ;
const CONFLICT = 408 ;
const GONE = 410 ;
const LENGTH_REQUIRED = 411 ;
const PRECONDITION_FAILED = 412 ;
const REQUEST_ENTITY_TOO_LARGE = 413 ;
const REQUESTURI_TOO_LARGE = 414 ;
const UNSUPPORTED_MEDIA_TYPE = 415 ;
const REQUESTED_RANGE_NOT_SATISFIABLE = 416 ;
const EXPECTATION_FAILED = 417 ;
const IM_A_TEAPOT = 418 ;
const INTERNAL_SERVER_ERROR = 500 ;
const NOT_IMPLEMENTED = 501 ;
const BAD_GATEWAY = 502 ;
const SERVICE_UNAVAILABLE = 503 ;
const GATEWAY_TIMEOUT = 504 ;
const HTTP_VERSION_NOT_SUPPORTED = 505 ;
>

if you need a response code not supported by http_response_code(), such as WebDAV / RFC4918’s «HTTP 507 Insufficient Storage», try:

( $_SERVER [ ‘SERVER_PROTOCOL’ ] . ‘ 507 Insufficient Storage’ );
?>
result: something like

HTTP/1.1 507 Insufficient Storage

The note above from «Anonymous» is wrong. I’m running this behind the AWS Elastic Loadbalancer and trying the header(‘:’.$error_code. ) method mentioned above is treated as invalid HTTP.

The documentation for the header() function has the right way to implement this if you’re still on ( «HTTP/1.0 404 Not Found» );
?>

At least on my side with php-fpm and nginx this method does not change the text in the response, only the code.

// HTTP/1.1 404 Not Found
http_response_code ( 404 );

?>

The resulting response is HTTP/1.1 404 OK

http_response_code is basically a shorthand way of writing a http status header, with the added bonus that PHP will work out a suitable Reason Phrase to provide by matching your response code to one of the values in an enumeration it maintains within php-src/main/http_status_codes.h. Note that this means your response code must match a response code that PHP knows about. You can’t create your own response codes using this method, however you can using the header method.

In summary — The differences between «http_response_code» and «header» for setting response codes:

1. Using http_response_code will cause PHP to match and apply a Reason Phrase from a list of Reason Phrases that are hard-coded into the PHP source code.

2. Because of point 1 above, if you use http_response_code you must set a code that PHP knows about. You can’t set your own custom code, however you can set a custom code (and Reason Phrase) if you use the header method.

It’s not mentioned explicitly, but the return value when SETTING, is the OLD status code.
e.g.
= http_response_code ();
$b = http_response_code ( 202 );
$c = http_response_code ();

var_dump ( $a , $b , $c );

http_response_code() does not actually send HTTP headers, it only prepares the header list to be sent later on.
So you can call http_reponse_code() to set, get and reset the HTTP response code before it gets sent.

http_response_code(500); // set the code
var_dump(headers_sent()); // check if headers are sent
http_response_code(200); // avoid a default browser page

On PHP 5.3 version, If you want to set HTTP response code. You can try this type of below trick 🙂

( ‘Temporary-Header: True’ , true , 404 );
header_remove ( ‘Temporary-Header’ );

@craig at craigfrancis dot co dot uk@ wrote the function that replaces the original. It is very usefull, but has a bug. The original http_response_code always returns the previous or current code, not the code you are setting now. Here is my fixed version. I also use $GLOBALS to store the current code, but trigger_error() instead of exit. So now, how the function will behave in the case of error lies on the error handler. Or you can change it back to exit().

if (!function_exists(‘http_response_code’)) <
function http_response_code($code = NULL) <
$prev_code = (isset($GLOBALS[‘http_response_code’]) ? $GLOBALS[‘http_response_code’] : 200);

if ($code === NULL) <
return $prev_code;
>

switch ($code) <
case 100: $text = ‘Continue’; break;
case 101: $text = ‘Switching Protocols’; break;
case 200: $text = ‘OK’; break;
case 201: $text = ‘Created’; break;
case 202: $text = ‘Accepted’; break;
case 203: $text = ‘Non-Authoritative Information’; break;
case 204: $text = ‘No Content’; break;
case 205: $text = ‘Reset Content’; break;
case 206: $text = ‘Partial Content’; break;
case 300: $text = ‘Multiple Choices’; break;
case 301: $text = ‘Moved Permanently’; break;
case 302: $text = ‘Moved Temporarily’; break;
case 303: $text = ‘See Other’; break;
case 304: $text = ‘Not Modified’; break;
case 305: $text = ‘Use Proxy’; break;
case 400: $text = ‘Bad Request’; break;
case 401: $text = ‘Unauthorized’; break;
case 402: $text = ‘Payment Required’; break;
case 403: $text = ‘Forbidden’; break;
case 404: $text = ‘Not Found’; break;
case 405: $text = ‘Method Not Allowed’; break;
case 406: $text = ‘Not Acceptable’; break;
case 407: $text = ‘Proxy Authentication Required’; break;
case 408: $text = ‘Request Time-out’; break;
case 409: $text = ‘Conflict’; break;
case 410: $text = ‘Gone’; break;
case 411: $text = ‘Length Required’; break;
case 412: $text = ‘Precondition Failed’; break;
case 413: $text = ‘Request Entity Too Large’; break;
case 414: $text = ‘Request-URI Too Large’; break;
case 415: $text = ‘Unsupported Media Type’; break;
case 500: $text = ‘Internal Server Error’; break;
case 501: $text = ‘Not Implemented’; break;
case 502: $text = ‘Bad Gateway’; break;
case 503: $text = ‘Service Unavailable’; break;
case 504: $text = ‘Gateway Time-out’; break;
case 505: $text = ‘HTTP Version not supported’; break;
default:
trigger_error(‘Unknown http status code ‘ . $code, E_USER_ERROR); // exit(‘Unknown http status code «‘ . htmlentities($code) . ‘»‘);
return $prev_code;
>

$protocol = (isset($_SERVER[‘SERVER_PROTOCOL’]) ? $_SERVER[‘SERVER_PROTOCOL’] : ‘HTTP/1.0’);
header($protocol . ‘ ‘ . $code . ‘ ‘ . $text);
$GLOBALS[‘http_response_code’] = $code;

// original function always returns the previous or current code
return $prev_code;
>
>

Источник

This is a short guide on how to send a 500 Internal Server Error header to the client using PHP. This is useful because it allows us to tell the client that the server has encountered an unexpected condition and that it cannot fulfill the request.

Below, I have created a custom PHP function called internal_error.

//Function that sends a 500 Internal Server Error status code to
//the client before killing the script.
function internal_error(){
    header($_SERVER["SERVER_PROTOCOL"] . ' 500 Internal Server Error', true, 500);
    echo '<h1>Something went wrong!</h1>';
    exit;
}

When the PHP function above is called, the script’s execution is halted and “Something went wrong!” is printed out onto the page.

Furthermore, if you inspect the HTTP headers with your browser’s developer console, you will see that the function is returning a 500 Internal Server Error status code:

To send the 500 status code, we used PHP’s header function like so:

//Send a 500 status code using PHP's header function
header($_SERVER["SERVER_PROTOCOL"] . ' 500 Internal Server Error', true, 500);

Note that we used the SERVER_PROTOCOL variable in this case because the client might be using HTTP 1.0 instead of HTTP 1.1. In other examples, you will find developers making the assumption that the client will always be using HTTP 1.1.

This is not the case.

The problem with PHP is that it doesn’t always send a 500 Internal Server Error when an exception is thrown or a fatal error occurs.

This can cause a number of issues:

1. It becomes more difficult to handle failed Ajax calls, as the server in question is still responding with a 200 OK status. For example: The JQuery Ajax error handling functions will not be called.
2. Search engines such as Google may index your error pages. If this happens, your website may lose its rankings.
3. Other HTTP clients might think that everything is A-OK when it is not.

Note that if you are using PHP version 5.4 or above, you can use the http_response_code function:

//Using http_response_code
http_response_code(500);

Far more concise!

<?php
    custom_header( "500 Internal Server Error" );

    if ( that_happened ) {
        die( "that happened" )
    }

    if ( something_else_happened ) {
        die( "something else happened" )
    }

    update_database( );

    // the script can also fail on the above line
    // e.g. a mysql error occurred

    remove_header( "500" );
?>

HTTP/1.1 500 No Record Found
HTTP/1.1 500 Script Generated Error (E_RECORD_NOT_FOUND)
HTTP/1.1 500 Conditions Failed on Line 23

header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error', true, 500);

http_response_code(500);

function header_status($statusCode) {
    static $status_codes = null;

    if ($status_codes === null) {
        $status_codes = array (
            100 => 'Continue',
            101 => 'Switching Protocols',
            102 => 'Processing',
            200 => 'OK',
            201 => 'Created',
            202 => 'Accepted',
            203 => 'Non-Authoritative Information',
            204 => 'No Content',
            205 => 'Reset Content',
            206 => 'Partial Content',
            207 => 'Multi-Status',
            300 => 'Multiple Choices',
            301 => 'Moved Permanently',
            302 => 'Found',
            303 => 'See Other',
            304 => 'Not Modified',
            305 => 'Use Proxy',
            307 => 'Temporary Redirect',
            400 => 'Bad Request',
            401 => 'Unauthorized',
            402 => 'Payment Required',
            403 => 'Forbidden',
            404 => 'Not Found',
            405 => 'Method Not Allowed',
            406 => 'Not Acceptable',
            407 => 'Proxy Authentication Required',
            408 => 'Request Timeout',
            409 => 'Conflict',
            410 => 'Gone',
            411 => 'Length Required',
            412 => 'Precondition Failed',
            413 => 'Request Entity Too Large',
            414 => 'Request-URI Too Long',
            415 => 'Unsupported Media Type',
            416 => 'Requested Range Not Satisfiable',
            417 => 'Expectation Failed',
            422 => 'Unprocessable Entity',
            423 => 'Locked',
            424 => 'Failed Dependency',
            426 => 'Upgrade Required',
            500 => 'Internal Server Error',
            501 => 'Not Implemented',
            502 => 'Bad Gateway',
            503 => 'Service Unavailable',
            504 => 'Gateway Timeout',
            505 => 'HTTP Version Not Supported',
            506 => 'Variant Also Negotiates',
            507 => 'Insufficient Storage',
            509 => 'Bandwidth Limit Exceeded',
            510 => 'Not Extended'
        );
    }

    if ($status_codes[$statusCode] !== null) {
        $status_string = $statusCode . ' ' . $status_codes[$statusCode];
        header($_SERVER['SERVER_PROTOCOL'] . ' ' . $status_string, true, $statusCode);
    }
}

<?php
header_status(500);

if (that_happened) {
    die("that happened")
}

if (something_else_happened) {
    die("something else happened")
}

update_database();

header_status(200);

header("HTTP/1.0 500 Internal Server Error");

if (that happened) {
    header("HTTP/1.0 500 Internal Server Error");
}

$result = mysql_query("..query string..") or header("HTTP/1.0 500 Internal Server Error");

if ( that_happened || something_else_happened )
{
    header('X-Error-Message: Incorrect username or password', true, 500);
    die;
}

HTTP/1.1 500 Internal Server Error
...
X-Error-Message: Incorrect username or password
...

if ( that_happened )
{
    header('X-Error-Message: Incorrect username', true, 500);
    die('Incorrect username');
}

if ( something_else_happened )
{
    header('X-Error-Message: Incorrect password', true, 500);
    die('Incorrect password');
}

<?php
if ( that_happened ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

if ( something_else_happened ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

// Your function should return FALSE if something goes wrong
if ( !update_database() ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

// the script can also fail on the above line
// e.g. a mysql error occurred


header('HTTP/1.1 200 OK');
?>

About the technologies asked in this question

PHP

PHP (from the English Hypertext Preprocessor — hypertext preprocessor) is a scripting programming language for developing web applications. Supported by most hosting providers, it is one of the most popular tools for creating dynamic websites.
The PHP scripting language has gained wide popularity due to its processing speed, simplicity, cross-platform, functionality and distribution of source codes under its own license.
https://www.php.net/

MySQL

DBMS is a database management system. It is designed to change, search, add and delete information in the database. There are many DBMSs designed for similar purposes with different features. One of the most popular is MySQL.
It is a software tool designed to work with relational SQL databases. It is easy to learn even for site owners who are not professional programmers or administrators. MySQL DBMS also allows you to export and import data, which is convenient when moving large amounts of information.
https://www.mysql.com/

HTML

HTML (English «hyper text markup language» — hypertext markup language) is a special markup language that is used to create sites on the Internet.
Browsers understand html perfectly and can interpret it in an understandable way. In general, any page on the site is html-code, which the browser translates into a user-friendly form. By the way, the code of any page is available to everyone.
https://www.w3.org/html/

• Как изменить код ответа сервера
• Если требуется перенаправить на другой url
• Заголовки кодировки и языка
• Модификация заголовков для управления контентом
• Как влиять на СЕО

При серьезной разработке сайта возникает необходимость выдавать корректные http заголовки php средствами.
Вы спросите — зачем? Затем, что корректность HTTP-заголовков влияет на то, как будут понимать поисковые роботы получаемую с вашего сайта информацию, что напрямую влияет на продвижение сайта, т.е. на «СЕО».

ВАЖНО ПОМНИТЬ!
мордифицировать HTTP header с помощью языка php возможно только если директива header выводится на клиента до формировании страницы, то есть до вывода любой иной инофрмации.
В противном случае назначение нового статуса HTTP заголовку / header выдает ошибку.

Как изменить код ответа сервера.

В большинстве случаев заголовки изменяются непосредственно в ваших php функциях (методах).

<?php
function checkUrl( $url )
{
   if( preg_match( «/^http.*/i», $url ) == false )
       header( ‘Location: http://www.ru/404.html’ );
}
…
?>

Рассмотрим несколько примеров модификации HTTP заголовков.

Страница выполнена корректно

header( ‘HTTP/1.1 200 OK’ );

Запрашиваемая страница не найдена

header( ‘HTTP/1.1 404 Not Found’ );

Доступ запрещен:

header( ‘HTTP/1.1 403 Forbidden’ );

Страница перемещена навсегда.

Используется для корректировки урлов поисковых серверов.

header( ‘HTTP/1.1 301 Moved Permanently’ );

Сервер выполнил скрипт с ошибкой

header( ‘HTTP/1.1 500 Internal Server Error’ );

Если требуется перенаправить на другой url

Перенаправление на указанный адресу

header( ‘Location: http://www.ru/’ );

Перенаправление на указанный адрес с задержкой в 5 секунд

в принципе это калька HTML тега
<meta http-equiv=»refresh» content=»5;http://www.ru/ />

header( ‘Refresh: 5; url=http://www.ru/’ );

Заголовки кодировки и языка

Содержимое страницы использует язык:

header( ‘Content-language: en’ ); // en = English

Как поменять кодировку

header(‘Content-Type: text/html; charset=utf-8’);

Модификация заголовков для управления контентом

header( ‘Content-Type: application/octet-stream’ );
header( ‘Content-Disposition: attachment; filename=»example.zip»‘ );
header( ‘Content-Transfer-Encoding: binary’ );

Установка content type

header(‘Content-Type: text/plain’); // plain text file
header(‘Content-Type: image/jpeg’); // JPG picture
header(‘Content-Type: audio/mpeg’); // Audio MPEG (MP3,…) file
header(‘Content-Type: application/x-shockwave-flash’); // Flash animation

Иные манипуляции с заголовками

как средствами php изменять header для поисковых роботов

Содержимое страницы последний раз изменялось

header( ‘Last-Modified: ‘.gmdate( ‘D, d M Y H:i:s’, ( time() — 60 ) ).’ GMT’ );

Длинна содержимого страницы

header( ‘Content-Length: 2048’ );

Отключение кеширования страницы:

header( ‘Cache-Control: no-cache, no-store, max-age=0, must-revalidate’ );
header( ‘Expires: Mon, 1 Apr 2001 01:02:03 GMT’ );
header( ‘Pragma: no-cache’ );

<?php

/*

参考自：

http://darklaunch.com/2010/09/01/http-status-codes-in-php-http-header-response-code-function

http://snipplr.com/view/68099/

*/

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],

);

}

/////////////////////////////////////////////////////////////////////////

// HTTP HEADER STATUS CODES

header(‘HTTP/1.1 200 OK’);

header(‘HTTP/1.1 404 Not Found’);

header(‘HTTP/1.1 403 Forbidden’);

header(‘HTTP/1.1 301 Moved Permanently’);

header(‘HTTP/1.1 304 Not Modified’);

header(‘HTTP/1.1 500 Internal Server Error’);

header(‘Location: http://www.example.org/’);

header(‘Refresh: 10; url=http://www.example.org/’);

print ‘You will be redirected in 10 seconds’;

// you can also use the HTML syntax:

// <meta http-equiv=»refresh» content=»10;http://www.example.org/ />

// override X-Powered-By value

header(‘X-Powered-By: PHP/4.4.0’);

// content language (en = English)

header(‘Content-language: en’);

// last modified (对缓存友好)

$time = time() — 60; // or filemtime($fn), etc

header(‘Last-Modified: ‘.gmdate(‘D, d M Y H:i:s’, $time).‘ GMT’);

// set content length (对缓存友好):

header(‘Content-Length: 1234’);

// Headers for an download:

header(‘Content-Type: application/octet-stream’);

header(‘Content-Disposition: attachment; filename=»example.zip»‘);

header(‘Content-Transfer-Encoding: binary’);

// load the file to send:

readfile(‘example.zip’);

// Disable caching of the current document:

header(‘Cache-Control: no-cache, no-store, max-age=0, must-revalidate’);

header(‘Expires: Mon, 26 Jul 1997 05:00:00 GMT’); // Date in the past

header(‘Pragma: no-cache’);

// set content type:

header(‘Content-Type: text/html; charset=iso-8859-1’);

header(‘Content-Type: text/html; charset=utf-8’);

header(‘Content-Type: text/plain’); // plain text file

header(‘Content-Type: image/jpeg’); // JPG picture

header(‘Content-Type: application/zip’); // ZIP file

header(‘Content-Type: application/pdf’); // PDF file

header(‘Content-Type: audio/mpeg’); // Audio MPEG (MP3,…) file

header(‘Content-Type: application/x-shockwave-flash’); // Flash animation

// show sign in box

header(‘HTTP/1.1 401 Unauthorized’);

header(‘WWW-Authenticate: Basic realm=»Top Secret»‘);

print ‘Text that will be displayed if the user hits cancel or enters wrong login data’;