ReflectionObject::export
The note about the signature of the ReflectionParameter constructor is actually incomplete, at least in 5.2.5: it is possible to use an integer for the second parameter, and the constructor will use it to return the n-th parameter.
This allows you to obtain proper ReflectionParameter objects even when documenting code from extensions which (strangely enough) define several parameters with the same name. The string-based constructor always returns the first parameter with the matching name, whereas the integer-based constructor correctly returns the n-th parameter.
So, in short, this works:
<?php
// supposing the extension defined something like:
// Some_Class::someMethod($a, $x, $y, $x, $y)
$p = new ReflectionParameter(array('Some_Class', 'someMethod'), 4);
// returns the last parameter, whereas
$p = new ReflectionParameter(array('Some_Class', 'someMethod'), 'y');
// always returns the first $y at position 2
?>
The ReflectionParameter class
(PHP 5)
Introduction
The ReflectionParameter class retrieves information about function's or method's parameters.
To introspect function parameters, first create an instance of the ReflectionFunction or ReflectionMethod classes and then use their ReflectionFunctionAbstract::getParameters() method to retrieve an array of parameters.
Class synopsis
Properties
- name
-
Name of the parameter. Read-only, throws ReflectionException in attempt to write.
Table of Contents
- ReflectionParameter::allowsNull — Checks if null is allowed
- ReflectionParameter::canBePassedByValue — Returns whether this parameter can be passed by value
- ReflectionParameter::__clone — Clone
- ReflectionParameter::__construct — Construct
- ReflectionParameter::export — Exports
- ReflectionParameter::getClass — Get class
- ReflectionParameter::getDeclaringClass — Gets declaring class
- ReflectionParameter::getDeclaringFunction — Gets declaring function
- ReflectionParameter::getDefaultValue — Gets default parameter value
- ReflectionParameter::getDefaultValueConstantName — Returns the default value's constant name if default value is constant or null
- ReflectionParameter::getName — Gets parameter name
- ReflectionParameter::getPosition — Gets parameter position
- ReflectionParameter::isArray — Checks if parameter expects an array
- ReflectionParameter::isCallable — Returns whether parameter MUST be callable
- ReflectionParameter::isDefaultValueAvailable — Checks if a default value is available
- ReflectionParameter::isDefaultValueConstant — Returns whether the default value of this parameter is constant
- ReflectionParameter::isOptional — Checks if optional
- ReflectionParameter::isPassedByReference — Checks if passed by reference
- ReflectionParameter::__toString — To string
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User Contributed Notes
ReflectionParameter - [3 notes]
fgm at riff dot org ¶
5 years ago
killgecNOFSPAM at gmail dot com ¶
5 years ago
Signature of constructor of ReflectionParameter correctly is:
public function __construct(array/string $function, string $name);
where $function is either a name of a global function, or a class/method name pair.
massimo at mmware dot it ¶
5 years ago
I found these limitations using class ReflectionParameter from ReflectionFunction with INTERNAL FUNCTIONS (eg print_r, str_replace, ... ) :
1. parameter names don't match with manual: (try example 19.35 with arg "call_user_func" )
2. some functions (eg PCRE function, preg_match etc) have EMPTY parameter names
3. calling getDefaultValue on Parameters will result in Exception "Cannot determine default value for internal functions"