PHP 8.4.0 RC4 available for testing

ob_get_level

(PHP 4 >= 4.2.0, PHP 5, PHP 7, PHP 8)

ob_get_levelReturn the nesting level of the output buffering mechanism

Description

ob_get_level(): int

Returns the nesting level of the output buffering mechanism.

Parameters

This function has no parameters.

Return Values

Returns the level of nested output buffering handlers or zero if output buffering is not active.

Caution

The value for identical levels between ob_get_level() and ob_get_status() is off by one. For ob_get_level() the first level is 1. Whereas for ob_get_status() the first level is 0.

See Also

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User Contributed Notes 3 notes

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55
Anonymous
12 years ago
For users confused about getting "1" as a return value from ob_get_level at the beginning of a script: this likely means the PHP ini directive "output_buffering" is not set to off / 0. PHP automatically starts output buffering for all your scripts if this directive is not off (which acts as if you called ob_start on the first line of your script).

If your scripts may end up on any server and you don't want end-users to have to configure their INI, you can use the following at the start of your script to stop output buffering if it's already started:
<?php
if (ob_get_level()) ob_end_clean();
?>

Alternatively, you can use the opposite if you always want to have an output buffer at the start of your script:
<?php
if (!ob_get_level()) ob_start();
?>
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10
Anonymous
9 years ago
This can be used to handle exceptions properly when using output buffering for rendering a view which may or may not be using output buffering

<?php

function getView($view)
{
$level = ob_get_level();

ob_start();

try
{
include
$view;
}

catch (
Exception $e)
{
while (
ob_get_level() > $level)
{
ob_end_clean();
}

throw
$e;
}

return
ob_get_clean();
}
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2
bonzini at gnu dot org
20 years ago
Even under older PHP, you can decide if output buffering is active (i.e. ob_get_level() > 0) using

<?php $ob_active = ob_get_length () !== FALSE ?>

Paolo
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