PHP Conference Nagoya 2025

ReflectionParameter::__construct

(PHP 5, PHP 7, PHP 8)

ReflectionParameter::__constructConstruct

Description

public ReflectionParameter::__construct(string|array|object $function, int|string $param)

Constructs a ReflectionParameter instance.

Parameters

function

The function to reflect parameters from.

param

Either an int specifying the position of the parameter (starting with zero), or the parameter name as string.

Examples

Example #1 Using the ReflectionParameter class

<?php
function foo($a, $b, $c) { }
function
bar(Exception $a, &$b, $c) { }
function
baz(ReflectionFunction $a, $b = 1, $c = null) { }
function
abc() { }

$reflect = new ReflectionFunction('foo');

echo
$reflect;

foreach (
$reflect->getParameters() as $i => $param) {
printf(
"-- Parameter #%d: %s {\n".
" Class: %s\n".
" Allows NULL: %s\n".
" Passed to by reference: %s\n".
" Is optional?: %s\n".
"}\n",
$i, // $param->getPosition() can be used
$param->getName(),
var_export($param->getClass(), 1),
var_export($param->allowsNull(), 1),
var_export($param->isPassedByReference(), 1),
$param->isOptional() ? 'yes' : 'no'
);
}
?>

The above example will output something similar to:

Function [ <user> function foo ] {
  @@ /Users/philip/cvs/phpdoc/a 2 - 2

  - Parameters [3] {
    Parameter #0 [ <required> $a ]
    Parameter #1 [ <required> $b ]
    Parameter #2 [ <required> $c ]
  }
}
-- Parameter #0: a {
   Class: NULL
   Allows NULL: true
   Passed to by reference: false
   Is optional?: no
}
-- Parameter #1: b {
   Class: NULL
   Allows NULL: true
   Passed to by reference: false
   Is optional?: no
}
-- Parameter #2: c {
   Class: NULL
   Allows NULL: true
   Passed to by reference: false
   Is optional?: no
}

See Also

add a note

User Contributed Notes 1 note

up
9
tracid2008 t gmail o com
12 years ago
You also can use a class instead of a function name. Just use an array like that
<?php
$reflect
= new ReflectionParameter(array('className', 'methodName'), 'property');
?>
To Top