Php/docs/function.var-export

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Variable handling Functions
Outputs or returns a parsable string representation of a variable

var_export

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

var_export — Outputs or returns a parsable string representation of a variable

Description

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

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 outputting 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 cannot be used inside an ob_start() callback function.

Changelog

Version	Description
7.3.0	Now exports stdClass objects as an array cast to an object (`(object) array( ... )`), rather than using the nonexistent method stdClass::__setState(). The practical effect is that now stdClass is exportable, and the resulting code will even work on earlier versions of PHP.

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

Example #2 Exporting stdClass (since PHP 7.3.0)

<?php$person = new stdClass;$person->name = 'ElePHPant ElePHPantsdotter';$person->website = 'https://php.net/elephpant.php';var_export($person);

The above example will output:

(object) array(
   'name' => 'ElePHPant ElePHPantsdotter',
   'website' => 'https://php.net/elephpant.php',
)

Example #3 Exporting classes (since PHP 5.1.0)

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

The above example will output:

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

Example #4 Using __set_state() (since PHP 5.1.0)

<?phpclass 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('$b = ' . var_export($a, true) . ';'); // $b = A::__set_state(array( // 'var1' => 5, // 'var2' => 'foo', // ));var_dump($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().

Warning When var_export() exports objects, the leading backslash is not included in the class name of namespaced classes for maximum compatibility.

Note:
To be able to evaluate the PHP generated by var_export(), all processed objects must implement the magic __set_state method. The only exception is stdClass, which is exported using an array cast to an object.

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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