PHP - Manual: var_representation
2024-11-13
(PECL var_representation >= 0.1.0)
var_representation — Returns a short, readable, parsable string representation of a variable
var_representation() (from the var_representation PECL) returns a string with structured information about the given variable. It is similar to var_export() with differences in indentation, string escaping, and array representations.
value
The variable to generate a representation of.
flags
Bitmask consisting of
VAR_REPRESENTATION_SINGLE_LINE
,
VAR_REPRESENTATION_UNESCAPED
.
The behaviour of these constants is described on the
var_representation constants page.
Returns the variable representation.
示例 #1 var_representation() Examples
<?php
$a = [1, 2, ['key' => 'value']];
echo var_representation($a), "\n";
echo var_representation($a, VAR_REPRESENTATION_SINGLE_LINE), "\n";
?>
以上例程会输出:
[ 1, 2, [ 'key' => 'value', ], ] [1, 2, ['key' => 'value']]
示例 #2 Escaping control characters
<?php
echo var_representation("Content-Length: 123\r\n");
以上例程会输出:
"Content-Length: 123\r\n"
示例 #3 Exporting stdClass
<?php
$person = new stdClass;
$person->name = 'ElePHPant ElePHPantsdotter';
$person->website = 'https://php.net/elephpant.php';
echo var_representation($person);
以上例程会输出:
(object) [ 'name' => 'ElePHPant ElePHPantsdotter', 'website' => 'https://php.net/elephpant.php', ]
示例 #4 Exporting classes
<?php
class A { public $var; }
$a = new A;
$a->var = 5;
echo var_representation($a);
?>
以上例程会输出:
\A::__set_state([ 'var' => 5, ])
示例 #5 Using __set_state()
<?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_representation($a) . ';'); // $b = \A::__set_state([
// 'var1' => 5,
// 'var2' => 'foo',
// ]);
var_dump($b);
?>
以上例程会输出:
object(A)#2 (2) { ["var1"]=> int(5) ["var2"]=> string(3) "foo" }
官方地址:https://www.php.net/manual/en/function.var-representation.php