Sometimes, ob_get_level() may be off by 1 because at the start of the script, it will return 1 even if ob_start() has never been called (and clearing the output buffer via ob_end_clean() and the like can be done without error). As a result, the first ob_start() will have an ob_get_level() of 2, the second will be 3, and so on.
I'm not sure if this is a PHP 5 thing or possibly because our server is set to gzip all html documents.
Also, up until at least PHP 5.0.4 (current version), ob_get_level() will always return 0 inside a destructor. This happens because the garbage collection for output buffers has already done before the destructor is called. If you want to do something with the output buffer from within an object before the script exits, using a callback function with ob_start() is the way to go.
ob_get_level
(PHP 4 >= 4.2.0, PHP 5)
ob_get_level — 出力バッファリング機構のネストレベルを返す
説明
int ob_get_level ( void )この関数は、出力バッファリングハンドラのネストレベルを返します。 バッファリングがアクティブでない場合はゼロを返します。
ob_start() および ob_get_contents() も参照ください。
ob_get_level
19-May-2005 12:45
bonzini at gnu dot org
08-Jul-2004 01:03
08-Jul-2004 01:03
Even under older PHP, you can decide if output buffering is active (i.e. ob_get_level() > 0) using
$ob_active = ob_get_length () !== FALSE
Paolo
tit dot petric at nospam dot telemach dot net
23-Jun-2002 04:01
23-Jun-2002 04:01
function condor_error($errno, $errstr, $errfile, $errline)
{
$errors = array(E_USER_ERROR, E_ERROR, E_PARSE);
if (in_array($errno,$errors)) {
while (ob_get_level()) {
ob_end_clean();
}
echo "<B>FATAL</B> [".$errno."] ".$errstr."<br>\n";
echo "Fatal error at line ".$errline." of file ".$errfile;
echo ", PHP ".PHP_VERSION." (".PHP_OS.")<br>\n";
echo "Aborting...<br><br>\n\n";
exit;
}
}
set_error_handler("condor_error");
in case you wanted to use a function to use for deleting all buffered output (to clearly display errors), you have it above
this eliminates the need for ob_end_clean_all() in php. good code :)