Перенаправление php. Как перенаправить пользователя на другую страницу? Использование функции PHP header() для редиректа URL-адреса

(PHP 4, PHP 5, PHP 7)

header — Send a raw HTTP header

Description

header (string $header [, bool $replace = TRUE [, int $http_response_code ]]) : void

header() is used to send a raw HTTP header. See the » HTTP/1.1 specification for more information on HTTP headers.

Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP. It is a very common error to read code with include , or require , functions, or another file access function, and have spaces or empty lines that are output before header() is called. The same problem exists when using a single PHP/HTML file.

/* This will give an error. Note the output
* above, which is before the header() call */
header ();
exit;
?>

Parameters

The header string.

There are two special-case header calls. The first is a header that starts with the string "HTTP/ " (case is not significant), which will be used to figure out the HTTP status code to send. For example, if you have configured Apache to use a PHP script to handle requests for missing files (using the ErrorDocument directive), you may want to make sure that your script generates the proper status code.

header ("HTTP/1.0 404 Not Found" );
?>

The second special case is the "Location:" header. Not only does it send this header back to the browser, but it also returns a REDIRECT (302) status code to the browser unless the 201 or a 3xx status code has already been set.

header ("Location: http://www.example.com/" ); /* Redirect browser */

/* Make sure that code below does not get executed when we redirect. */
exit;
?>

Replace

The optional replace parameter indicates whether the header should replace a previous similar header, or add a second header of the same type. By default it will replace, but if you pass in FALSE as the second argument you can force multiple headers of the same type. For example:

header ("WWW-Authenticate: Negotiate" );
header ("WWW-Authenticate: NTLM" , false );
?>

Http_response_code

Forces the HTTP response code to the specified value. Note that this parameter only has an effect if the header is not empty.

Return Values

No value is returned.

Changelog

Examples

Example #1 Download dialog

If you want the user to be prompted to save the data you are sending, such as a generated PDF file, you can use the » Content-Disposition header to supply a recommended filename and force the browser to display the save dialog.

// We"ll be outputting a PDF
header ("Content-Type: application/pdf" );

// It will be called downloaded.pdf
header ("Content-Disposition: attachment; filename="downloaded.pdf"" );

// The PDF source is in original.pdf
readfile ("original.pdf" );
?>

Example #2 Caching directives

PHP scripts often generate dynamic content that must not be cached by the client browser or any proxy caches between the server and the client browser. Many proxies and clients can be forced to disable caching with:

header ("Cache-Control: no-cache, must-revalidate" ); // HTTP/1.1
header ("Expires: Sat, 26 Jul 1997 05:00:00 GMT" ); // Date in the past
?>

You may find that your pages aren"t cached even if you don"t output all of the headers above. There are a number of options that users may be able to set for their browser that change its default caching behavior. By sending the headers above, you should override any settings that may otherwise cause the output of your script to be cached.

«An obsolete version of the HTTP 1.1 specifications (IETF RFC 2616) required a complete absolute URI for redirection. The IETF HTTP working group found that the most popular web browsers tolerate the passing of a relative URL and, consequently, the updated HTTP 1.1 specifications (IETF RFC 7231) relaxed the original constraint, allowing the use of relative URLs in Location headers.»

Workaround: do not send those headers.

Also, be aware that IE versions 5, 6, 7, and 8 double-compress already-compressed files and do not reverse the process correctly, so ZIP files and similar are corrupted on download.

Workaround: disable compression (beyond text/html) for these particular versions of IE, e.g., using Apache"s "BrowserMatch" directive. The following example disables compression in all versions of IE:

BrowserMatch ".*MSIE.*" gzip-only-text/html

4. Relative URIs are NOT allowed

wrong: Location: /something.php?a=1
wrong: Location: ?a=1

It will make proxy server and http clients happier.

15 years ago

If you haven"t used, HTTP Response 204 can be very convenient. 204 tells the server to immediately termiante this request. This is helpful if you want a javascript (or similar) client-side function to execute a server-side function without refreshing or changing the current webpage. Great for updating database, setting global variables, etc.

Header("status: 204"); (or the other call)
header("HTTP/1.0 204 No Response");

15 years ago

A call to session_write_close() before the statement

header ("Location: URL" );
exit();
?>
is recommended if you want to be sure the session is updated before proceeding to the redirection.

We encountered a situation where the script accessed by the redirection wasn"t loading the session correctly because the precedent script hadn"t the time to update it (we used a database handler).

9 months ago

// Beware that adding a space between the keyword "Location" and the colon causes an Internal Sever Error

//This line causes the error
7
header("Location: index.php&controller=produit&action=index");

// While It must be written without the space
header("Location: index.php&controller=produit&action=index");

1 year ago

The header call can be misleading to novice php users.
when "header call" is stated, it refers the the top leftmost position of the file and not the "header()" function itself.
"

10 years ago

Here is a php script I wrote to stream a file and crypt it with a xor operation on the bytes and with a key:

The encryption works very good but the speed is decrease by 2, it is now 520KiB/s. The user is now asked for a md5 password (instead of keeping it in the code directly). There is some part in French because it"s my native language so modify it as you want.

// Stream files and encrypt the data on-the-fly

// Settings
// -- File to stream
$file = "FILE_out" ;
// -- Reading buffer
$bufferlength = 3840 ;
// -- Key in hex
//$keychar = "9cdfb439c7876e703e307864c9167a15";

// Function: Convertion hex key in a string into binary
function hex2bin ($h ) {
if (! is_string ($h )) return null ;
$r = array();
for ($a = 0 ; ($a * 2 )< strlen ($h ); $a ++) {
$ta = hexdec ($h [ 2 * $a ]);
$tb = hexdec ($h [(2 * $a + 1 )]);
$r [ $a ] = (int) (($ta << 4 ) + $tb );
}
return $r ;
}

// Function to send the auth headers
function askPassword ($text = "Enter the password" ) {
header ("WWW-Authenticate: Basic realm="" . utf8_decode ($text ) . """ );
header ("HTTP/1.0 401 Unauthorized" );
return 1 ;
}

// Key is asked at the first start
if (!isset($_SERVER [ "PHP_AUTH_PW" ])) {
askPassword ();
echo "Une clé est nécessaire !
" ;
exit;
}
// Get the key in hex
$keychar = $_SERVER [ "PHP_AUTH_PW" ];

// Convert key and set the size of the key
$key = hex2bin ($keychar );
$keylength = count ($key );
// Teste si la clé est valide en hex
if ($key == "" || $keylength <= 4 ) {
askPassword ("Clé incorrecte !" );
//echo "Clé incorrecte !
";
exit();
}
// Teste si la clé est de longueur d"une puissance de 2
if (($keylength % 2 ) != 0 ) {
askPassword ("Clé de longueur incorrecte (multiple de 2 uniquement)" );
//echo "Clé de longueur incorrecte (puissance de 2 uniquement)
";
exit();
}

// Headers
header ("Content-Type: application/octet-stream; " );
header ("Content-Transfer-Encoding: binary" );
header ("Content-Length: " . filesize ($file ) . "; " );
header ("filename=\"" . $file . "\"; " );
flush (); // this doesn"t really matter.

// Opening the file in read-only
$fp = fopen ($file , "r" );
while (! feof ($fp ))
{
// Read a buffer size of the file
$buffer = fread ($fp , $bufferlength );
$j = 0 ;
for ($i = 0 ; $i < $bufferlength ; $i ++) {
// The key is read in loop to crypt the whole file
if ($i % $keylength == 0 ) {
$j = 0 ;
}
// Apply a xor operation between the key and the file to crypt
// This operation eats a lots of CPU time (Stream at 1MiB/s on my server; Intel E2180)
$tmp = pack ("C" , $key [ $j ]);
$bufferE = ($buffer [ $i ]^ $tmp ); // <==== Le fameux XOR

/*
echo "
key[".$j."]: ";
var_dump($tmp);
echo "
buffer[".$i."]: ";
var_dump($buffer[$i]);
echo "
bufferE: ";
var_dump($bufferE);
echo "
";
//*/

// Send the encrypted data
echo $bufferE ;
// Clean the memory
$bufferE = "" ;
$j ++;
}
$buffer = "" ;
flush (); // this is essential for large downloads
/*
fclose($fp);
exit();
//*/
}
// Close the file and it"s finished
fclose ($fp );

Быстрая навигация по этой странице:

Если вы решили написать скрипт и сделать редирект PHP, преимущества этого шага очевидны: PHP – серверно ориентированный язык скриптов; перенаправление будет выполняться посредством скрипта на сервере, а не в браузере посетителей. Некоторые перенаправления могут быть выполнены на стороне клиента — через редирект js (то есть через JavaScript редирект).

Это более гибкий и универсальный подход, и вы можете выполнить несколько типов редиректа в PHP, в отличие от других методов. Вот — наиболее частые виды редиректа, которые можно сделать в PHP: a) 301 редирект PHP (статус постоянного перенаправления), b) 302 редирект PHP (временный статус переадресации), с) Обновление.

Эта статья будет полезна, в первую очередь, для начинающих веб-мастеров, которые ищут способы реализации перенаправления URL, если это не возможно с использованием других распространенных решений, таких как Htaccess.

Заголовок языка PHP функции

Например, предположим, вы хотите сделать редирект к этому URL http://www.somewebsite.com/target.php. В исходном PHP страницы, Вам просто следует вызвать этот скрипт редиректа:

Попробуйте также провести этот простой эксперимент на вашем локальном хостинге:

1) Откройте текстовый редактор и введите этот код:

Сохраните его как targetpage.php.

2) Откройте другой пустой текстовый файл и введите этот код:

Сохраните его как originatingpage.php.

3) Теперь запустите веб-браузер. В адресной строке браузера введите: http://localhost/originatingpage.php

4) Вы заметите, что после нажатия кнопки ввода, этот URL: http://localhost/originatingpage.php делает редирект на http://localhost/targetpage.php и на targetpage.php, и вы видите слова «Hi this is codex-x».

Одна из самых распространенных ошибок может крыться в оформлении кода html редиректа:

Попробуйте выполнить этот эксперимент:

Перейдите к скрипту originatingpage.php и добавьте любой HTML тег:

header(‘Location: http://localhost/targetpage.php’);

Предположим, у вас есть такой код: