PHP: var_export

Examples

Example 1. var_export() Examples

<?php $a = array (1, 2, array ("a", "b", "c")); var_export($a); ?>
The above example will output:
array ( 0 => 1, 1 => 2, 2 => array ( 0 => 'a', 1 => 'b', 2 => 'c', ), )

<?php $b = 3.1; $v = var_export($b, true); echo $v; ?>
The above example will output:
3.1

User Contributed Notes
var_export

roman at DIESPAM dot feather dot org dot ru
18-Mar-2005 03:46


Function that exports variables without adding any junk to the resulting string:

<?php

function encode($var){

    if (is_array($var)) {

        $code = 'array(';

        foreach ($var as $key => $value) {

            $code .= "'$key'=>".encode($value).',';

        }

        $code = chop($code, ','); //remove unnecessary coma

        $code .= ')';

        return $code;

    } else {

        if (is_string($var)) {

            return "'".$var."'";

        } elseif (is_bool($code)) {

            return ($code ? 'TRUE' : 'FALSE');

        } else {

            return 'NULL';

        }

    }

}



function decode($string){

    return eval('return '.$string.';');

}

?>

The resulting string can sometimes be smaller, that output of serialize(). May be useful for storing things in the database.

paul at worldwithoutwalls dot co dot uk
24-Nov-2004 01:22


var_export() differs from print_r() for variables that are resources, with print_r() being more useful if you are using the function for debugging purposes.

e.g.

<?php

$res = mysql_connect($dbhost, $dbuser, $dbpass);

print_r($res); //output: Resource id #14

var_export($res); //output: NULL

?>

aidan at php dot net
10-Jun-2004 11:53


This functionality is now implemented in the PEAR package PHP_Compat.



More information about using this function without upgrading your version of PHP can be found on the below link:



http://pear.php.net/package/PHP_Compat

webmaster at huinca dot net
26-Oct-2003 01:11


(Regarding a previous post in this page)



Please keep in mind that $GLOBALS is a quite unique type of array, where nesting level are infinite because $GLOBALS['GLOBALS'] is exactly $GLOBALS (and recursively). Thus, 



// Never try these ones!

var_export($GLOBALS);

var_dump($GLOBALS);



yields a nesting level very, very deep. As deep as you want :) So, to check recursivity please choose any other variable.

php_manual_note at bigredspark dot com
16-Oct-2003 02:43


[john holmes]


True, but that method would require you to open and read the file into a variable and then unserialize it into another variable.





Using a file created with var_export() could simply be include()'d, which will be less code and faster. 





[kaja]


If you are trying to find a way to temporarily save variables into some other file, check out serialize() and unserialize() instead - this one is more useful for its readable property, very handy while debugging.





[original post]


If you're like me, you're wondering why a function that outputs "correct PHP syntax" is useful. This function can be useful in implementing a cache system. You can var_export() the array into a variable and write it into a file. Writing a string such as





<?php


$string = '<?php $array = ' . $data . '; ?>';


?>





where $data is the output of var_export() can create a file that can be easily include()d back into the script to recreate $array. 





The raw output of var_export() could also be eval()d to recreate the array.





---John Holmes...

var_export

Description

Parameters

Return Values

Examples

See Also