This is an example of how the stack works:
<?php
//Level 0
ob_start();
echo "Hello ";
//Level 1
ob_start();
echo "Hello World";
$out2 = ob_get_contents();
ob_end_clean();
//Back to level 0
echo "Galaxy";
$out1 = ob_get_contents();
ob_end_clean();
//Just output
var_dump($out1, $out2);
?>
ob_get_contents
(PHP 4, PHP 5, PHP 7, PHP 8)
ob_get_contents — Retourne le contenu du tampon de sortie
Liste de paramètres
Cette fonction ne contient aucun paramètre.
Valeurs de retour
Retourne le contenu du tampon de sortie sans l'effacer
ou false, si la temporisation de sortie n'est pas activée.
Exemples
Exemple #1 Exemple avec ob_get_contents()
<?php
ob_start();
echo "Bonjour ";
$out1 = ob_get_contents();
echo "le monde !";
$out2 = ob_get_contents();
ob_end_clean();
var_dump($out1, $out2);
?>L'exemple ci-dessus va afficher :
string(8) "Bonjour " string(18) "Bonjour le monde !"
Voir aussi
- ob_start() - Enclenche la temporisation de sortie
- ob_get_length() - Retourne la longueur du contenu du tampon de sortie
add a note
User Contributed Notes 6 notes
mauroasprea+php at gmail dot com ¶
13 years ago
Mark Clements ¶
10 years ago
Note that, unlike PHP variables which make efficient use of memory, getting the contents of the output buffer results in a new copy of the buffer being made. This can end up massively increasing the memory requirements of your script if your output is large.
Example code:
<?php
print(memory_get_usage() . "<br>");
ob_start();
for ($i = 0; $i < 5000000; $i++)
print(" ");
print(memory_get_usage() . "<br>");
$foo = ob_get_contents();
print(memory_get_usage() . "<br>");
ob_end_flush();
?>
Output:
351664
5359152
10359256
ipfound at gmail dot com ¶
10 years ago
The ob_get_contents() function has different return behaivor in PHP 5.3.x and PHP 5.5.x. Take a look at very simple example for PHP 5.3
<?php
var_dump(ob_get_contents());
?>
Output: bool(false)
but in PHP 5.5.x, the same php code will return:
Output: string (0) ""
Actually, we can use type regulation - intval(ob_get_contents()), for cheking On/Off output buffering, but it lays the possible problems in the future.
DrDreistein at dontknow dot at ¶
13 years ago
i made a simple test which is faster: adding some text in the normal way or by the ob stack:
<?php
$start = microtime(true);
$var = '';
for($i=0 ; $i <= 1000000 ; $i++) {
$var .= ' ';
}
$middle = microtime(true);
ob_start();
for($i=0 ; $i <= 1000000 ; $i++) {
echo ' ';
}
$var = ob_get_contents();
ob_end_clean();
$end = microtime(true);
echo $middle - $start;
echo '<br />';
echo $end - $middle;
?>
Outputs something like this:
0.33658003807068
0.30778789520264
m227 ( at ) poczta dot onet dot pl ¶
19 years ago
if you use ob_start with a callback function as a parameter, and that function changes ob string (as in example in manual) don't expect that ob_get_contents will return changed ob.
it will work as you would use ob_start with no parameter at all. So don't be confused.
http://www.francescosaf.altervista.org ¶
19 years ago
transfer image, another method (alternative to fsockopen or function socket) :
server(192.168.0.1)
makeimage.php
...........
...........
$nameimage="xxxx.jpg"
$comand=exec("plotvelocity.sh $nameimage $paramater1 $paramater2");
ob_start();
readfile($nameimage);
$image_data = ob_get_contents();
ob_end_clean();
echo $image_data;
unlink($nameimage);
Client (192.168.0.2)
$bild="images/newimage2.gif";
$host="192.168.0.1";
$url=file_get_contents("http://$host/makeimage.php?$querystring");
$fp = fopen("$bild", 'wb');
fwrite($fp, $url);
fclose($fp);
echo '<img src="'.$bild.'">';
naturally you can transfer whichever thing and not only images
