I think a more accurate explanation is this:
The Reflection classes are designed to reflect upon the source code of an application, not on any runtime information.
I think you misunderstand the ReflectionProperty constructor in your example above. The fact that it accepts an object as argument is just a convenience feature - you are actually inspecting the class of that object, not the object itself, so it's basically equivalent to:
<?php
// works fine
$Reflection = new ReflectionProperty(get_class($a), 'a');
// throws exception
$Reflection = new ReflectionProperty(get_class($a), 'foo');
?>
Getting the class of the object you're passing in is implied, since inspecting a defined property is the purpose of this class.
In your example, $a->foo is a dynamic member - it is not defined as a member of class, so there is no defining class reference, line number, default value, etc. - which means, there is nothing to reflect upon.
Clearly this very useful library could use some real documentation...
The ReflectionProperty class
(PHP 5, PHP 7)
소개
The ReflectionProperty class reports information about classes properties.
클래스 개요
프로퍼티
- name
-
Name of the property. Read-only, throws ReflectionException in attempt to write.
- class
-
Name of the class where the property is defined. Read-only, throws ReflectionException in attempt to write.
Table of Contents
- ReflectionProperty::__clone — Clone
- ReflectionProperty::__construct — Construct a ReflectionProperty object
- ReflectionProperty::export — Export
- ReflectionProperty::getDeclaringClass — Gets declaring class
- ReflectionProperty::getDocComment — Gets the property doc comment
- ReflectionProperty::getModifiers — Gets modifiers
- ReflectionProperty::getName — Gets property name
- ReflectionProperty::getValue — Gets value
- ReflectionProperty::isDefault — Checks if property is a default property
- ReflectionProperty::isPrivate — Checks if property is private
- ReflectionProperty::isProtected — Checks if property is protected
- ReflectionProperty::isPublic — Checks if property is public
- ReflectionProperty::isStatic — Checks if property is static
- ReflectionProperty::setAccessible — Set property accessibility
- ReflectionProperty::setValue — Set property value
- ReflectionProperty::__toString — To string
add a note
User Contributed Notes 2 notes
rasmus at mindplay dot dk ¶
14 years ago
Nanhe Kumar ¶
10 years ago
<?php
//serialize static properties (class variable)
class Student {
private $members = array();
protected $name;
public static $noOfStudent;
public function __construct($name = 'Nanhe Kumar') {
$this->name = $name;
Student::$noOfStudent++;
}
public function __sleep() {
$vars = get_class_vars(get_class($this));
foreach ($vars as $key => $val) {
if (!empty($val))
$this->members[$key] = $val;
}
return array_keys(get_object_vars($this));
}
public function __wakeup() {
foreach ($this->members as $key => $val) {
$prop = new ReflectionProperty(get_class($this), $key);
$prop->setValue(get_class($this), $val);
}
$this->members = array();
}
public function getTotalStudent() {
return self::$noOfStudent;
}
}
$so1 = new Student();
$so2 = new Student();
$serialized = serialize($so1);
print_r($serialized); //O:7:"Student":2:{s:16:"Studentmembers";a:1:{s:11:"noOfStudent";i:2;}s:7:"*name";s:11:"Nanhe Kumar";}
$unserialized = unserialize($serialized);
print_r($unserialized); //Student Object ( [members:Student:private] => Array ( ) [name:protected] => Nanhe Kumar )
echo Student::$noOfStudent; //2
?>
