简体   繁体   中英

trying to understand ReflectionClass in php

<?php
interface NSerializable
{
// ...
}
class Object
{
// test...
}
/**
* A counter class test
*/
class Counter extends Object implements NSerializable
{
const START = 0;
private static $c = Counter::START;
/**
* Invoke counter test
*
* @access public
* @return int
*/
public function count()
{
return self::$c++;
}
}
// Create an instance of the ReflectionClass class
$class = new ReflectionClass('Counter');
// Print out basic information
printf(
"===> The %s%s%s %s '%s' [extends %s]\n" .
" declared in %s\n" .
" lines %d to %d\n" .
" having the modifiers %d [%s]\n",
$class->isInternal() ? 'internal' : 'user-defined',
$class->isAbstract() ? ' abstract' : '',
$class->isFinal() ? ' final' : '',
$class->isInterface() ? 'interface' : 'class',
$class->getName(),
var_export($class->getParentClass(), 1),
$class->getFileName(),
$class->getStartLine(),
$class->getEndline(),
$class->getModifiers(),
implode(' ', Reflection::getModifierNames(
$class->getModifiers()))
);
// Print documentation comment
printf("---> Documentation:\n %s\n",
var_export($class->getDocComment(), 1));
// Print which interfaces are implemented by this class
printf("---> Implements:\n %s\n",
var_export($class->getInterfaces(), 1));
// Print class constants
printf("---> Constants: %s\n",
var_export($class->getConstants(), 1));
// Print class properties
printf("---> Properties: %s\n",
var_export($class->getProperties(), 1));
// Print class methods
printf("---> Methods: %s\n",
var_export($class->getMethods(), 1));
// If this class is instantiable, create an instance
if ($class->isInstantiable())
{
$counter = $class->newInstance();
echo '---> $counter is instance? ';
echo $class->isInstance($counter) ? 'yes' : 'no';
echo "\n---> new Object() is instance? ";
echo $class->isInstance(new Object()) ? 'yes' : 'no';
}
?>

Questions:

  1. var_export($class->getParentClass(), 1) , output is: ===> The user-defined class 'Counter' [extends ReflectionClass::__set_state(array( 'name' => 'Object', ))]... var_export($class->getParentClass()) , output is: ReflectionClass::__set_state(array( 'name' => 'Object', ))===> The user-defined class 'Counter' [extends ]... why?

  2. $class->getParentClass() , output is: ReflectionClass::__set_state(array( 'name' => 'Object', )) what does this mean: '__set_state'?

  3. getModifiers() , getModifierNames() what does these two functions actually mean?

Answers 1. and 2.:

$class->getParentClass() is actually an object of type ReflectionClass not a string.

Replace:

var_export($class->getParentClass())

by:

$class->getParentClass()->getName()

3 . There is not method ReflectionClass::getModifierNames() . I don't know where you got this information from, but if you need it you'll have to write your own. Here comes an example that extends ReflectionClass and adds the method:

class MyReflectionClass extends ReflectionClass 
{

    /**
     * Returns the modifiers in human readable format
     */
    public function getModifierNames() {
        $m = $this->getModifiers();
        $names = array();
        if($m & self::IS_EXPLICIT_ABSTRACT === self::IS_EXPLICIT_ABSTRACT
        || $m & self::IS_IMPLICIT_ABSTRACT === self::IS_IMPLICIT_ABSTRACT) {
            $names []= 'abstract';
        }
        if($m & self::IS_FINAL === self::IS_FINAL) {
            $names []= 'final';
        }

        return implode(' ', $names);
    }

}

Use:

abstract class Counter extends Object 
  implements NSerializable
{ // ...

or

final class Counter extends Object 
  implements NSerializable
{ // ...

and

$class = new MyReflectionClass('Counter');

to test it

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM