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PHP Manual


var_export

(PHP 4 >= 4.2.0, PHP 5)

var_exportOutputs or returns a parsable string representation of a variable

Description

mixed var_export ( mixed $expression [, bool $return = false ] )

var_export() gets structured information about the given variable. It is similar to var_dump() with one exception: the returned representation is valid PHP code.

Parameters

expression

The variable you want to export.

return

If used and set to TRUE, var_export() will return the variable representation instead of outputing it.

Return Values

Returns the variable representation when the return parameter is used and evaluates to TRUE. Otherwise, this function will return NULL.

Notes

Note:

When the return parameter is used, this function uses internal output buffering so it can not be used inside an ob_start() callback function.

Changelog

Version Description
5.1.0 Possibility to export classes and arrays containing classes using the __set_state() magic method.

Examples

Example #1 var_export() Examples

<?php
$a 
= array (12, array ("a""b""c"));
var_export($a);
?>

The above example will output:

array (
  0 => 1,
  1 => 2,
  2 => 
  array (
    0 => 'a',
    1 => 'b',
    2 => 'c',
  ),
)
<?php

$b 
3.1;
$v var_export($btrue);
echo 
$v;

?>

The above example will output:

3.1

Example #2 Exporting classes since PHP 5.1.0

<?php
class { public $var; }
$a = new A;
$a->var 5;
var_export($a);
?>

The above example will output:

A::__set_state(array(
   'var' => 5,
))

Example #3 Using __set_state() (since PHP 5.1.0)

<?php
class A
{
    public 
$var1;
    public 
$var2;

    public static function 
__set_state($an_array)
    {
        
$obj = new A;
        
$obj->var1 $an_array['var1'];
        
$obj->var2 $an_array['var2'];
        return 
$obj;
    }
}

$a = new A;
$a->var1 5;
$a->var2 'foo';

eval(
'$b = ' var_export($atrue) . ';'); // $b = A::__set_state(array(
                                            //    'var1' => 5,
                                            //    'var2' => 'foo',
                                            // ));
var_dump($b);
?>

The above example will output:

object(A)#2 (2) {
  ["var1"]=>
  int(5)
  ["var2"]=>
  string(3) "foo"
}

Notes

Note:

Variables of type resource couldn't be exported by this function.

Note:

var_export() does not handle circular references as it would be close to impossible to generate parsable PHP code for that. If you want to do something with the full representation of an array or object, use serialize().

See Also

  • print_r() - Prints human-readable information about a variable
  • serialize() - Generates a storable representation of a value
  • var_dump() - Dumps information about a variable




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