(PHP 4, PHP 5, PHP 7, PHP 8)
ob_end_flush — Flush (send) the return value of the active output handler and turn the active output buffer off
This function calls the output handler
(with the PHP_OUTPUT_HANDLER_FINAL flag),
flushes (sends) it's return value,
discards the contents of the active output buffer
and turns off the active output buffer.
ob_end_flush() will fail
without an active output buffer started with the
PHP_OUTPUT_HANDLER_REMOVABLE flag.
ob_end_flush() will flush (send)
the return value of the output handler
even if the active output buffer was started without the
PHP_OUTPUT_HANDLER_FLUSHABLE flag.
This function has no parameters.
If the function fails it generates an E_NOTICE .
Example #1 ob_end_flush() example
The following example shows an easy way to flush and end all output buffers:
<?php
while (@ob_end_flush());
?>
A note on the above example...
with PHP 4 >= 4.2.0, PHP 5 you can use a combination of ob_get_level() and ob_end_flush() to avoid using the @ (error suppresion) which should probably be a little faaster.
<?php
while (ob_get_level() > 0) {
ob_end_flush();
}
?>best way to compress a css code:
<?php
header('Content-type: text/css');
ob_start("compress");
function compress($buffer) {
// remove comments
$buffer = preg_replace('!/\*[^*]*\*+([^/][^*]*\*+)*/!', '', $buffer);
// remove tabs, spaces, newlines, etc.
$buffer = str_replace(array("\r\n", "\r", "\n", "\t", ' ', ' ', ' '), '', $buffer);
return $buffer;
}
include('./template/main.css');
include('./template/classes.css');
<?php
ob_end_flush();
?>
Include in <head>:
<link rel="stylesheet" type="text/css" href="/design.php" media="all" />If you enable zlib.output_compression then level count will be increased by 1 and then this code:
<?php while (ob_get_level()) { ob_end_clean(); } ?>
will just freeze your script.Wanted to speed things up and put some processing after the page has been delivered to the client. That drove me almost insane, but finally, I found a solution (php 5.2.5):
<?php
ob_start(); // outer buffer
ob_start(); // inner buffer to catch URL rewrites and other post processing
session_start(); // registers URL rewriter with inner buffer!
echo '...';
// log performance data to log files *after* delivering the page!
register_shutdown_function(array($benchmarkclass,'log_perf_data'));
// now flush output output to client
ob_end_flush();
// need to calculate content length *after* URL rewrite!
header("Content-length: ".ob_get_length());
ob_end_flush();
// now we close the session and do some arbitrary clean-up tasks
// registered using register_shutdown_function()
session_write_close();
?>It appears that you can call ob_end_flush() regardless of whether or not output buffering was ever started using ob_start(). This can prove useful because it saves you from having to create conditional statements based on whether a particular function or include file has started output buffering. You can simply call the ob_end_flush() anyway and if there's output in the buffer, it will be sent, otherwise your script will just keep on keepin' on.Apart from being mostly redundant, ob_end_flush() can be downright damaging in some weird cases.
Actual example: a particular page on an Intranet website which would appear blank on Internet Explorer 6 when ob_start('ob_gzhandler') was called in the beginning and ob_end_flush() at the end.
We couldn't figure out what made that page special no matter what we tried. The ob_ functions were placed in scripts which were include()'d by all pages just the same, but only that page did this.
Even stranger, the problem only appeared on direct browser/server connections. Whenever the connection passed through a proxy the problem dissapeared. I'm guessing some kind of HTTP encoding headers mumbo-jumbo.
Solution: unless you really need it in particular cases, remove the ob_end_flush() call and rely on the builtin, automatic buffer flush.