ob_get_level

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

ob_get_level — Return the nesting level of the output buffering mechanism

Опис

ob_get_level(): int

Returns the nesting level of the output buffering mechanism.

Параметри

У цієї функції немає параметрів.

Значення, що повертаються

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

Застереження

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.

Прогляньте також

ob_start() - Turn on output buffering
ob_get_status() - Get status of output buffers
ob_get_contents() - Return the contents of the output buffer

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User Contributed Notes 3 notes

down

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();
?>

down

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();
}

down

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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