print_r. Руководство по PHP - Портал Сетевых Проектов.

Description

bool print_r ( mixed expression [, bool return] )

Замечание: The return parameter was added in PHP 4.3.0

print_r() displays information about a variable in a way that's readable by humans. If given a string, integer or float, the value itself will be printed. If given an array, values will be presented in a format that shows keys and elements. Similar notation is used for objects. print_r() and var_export() will also show protected and private properties of objects with PHP 5, on the contrary to var_dump().

Remember that print_r() will move the array pointer to the end. Use reset() to bring it back to beginning.


<pre>
<?php
    $a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x', 'y', 'z'));
    print_r ($a);
?>
</pre>

Результат выполнения данного примера:

<pre>
Array
(
[a] => apple
[b] => banana
[c] => Array
(
[0] => x
[1] => y
[2] => z
)
)
</pre>

If you would like to capture the output of print_r(), use the return parameter. If this parameter is set to TRUE, print_r() will return its output, instead of printing it (which it does by default).

Пример 1. return parameter example
<?php $b = array ('m' => 'monkey', 'foo' => 'bar', 'x' => array ('x', 'y', 'z')); $results = print_r($b, true); //$results now contains output from print_r ?>

Замечание: If you need to capture the output of print_r() with a version of PHP prior to 4.3.0, use the output-control functions.

Замечание: Prior to PHP 4.0.4, print_r() will continue forever if given an array or object that contains a direct or indirect reference to itself. An example is print_r($GLOBALS) because $GLOBALS is itself a global variable that contains a reference to itself.