ReflectionProperty::__construct

(PHP 5, PHP 7, PHP 8)

ReflectionProperty::__construct — Construct a ReflectionProperty object

说明

public ReflectionProperty::__construct(object|string $class, string $property)

参数

class

Either a string containing the name of the class to reflect, or an object.

property

The name of the property being reflected.

错误／异常

Trying to get or set private or protected class property's values will result in an exception being thrown.

范例

示例 #1 ReflectionProperty::__construct() example

<?php
class Str
{
    public $length  = 5;
}

// Create an instance of the ReflectionProperty class
$prop = new ReflectionProperty('Str', 'length');

// Print out basic information
printf(
    "===> The%s%s%s%s property '%s' (which was %s)\n" .
    "     having the modifiers %s\n",
        $prop->isPublic() ? ' public' : '',
        $prop->isPrivate() ? ' private' : '',
        $prop->isProtected() ? ' protected' : '',
        $prop->isStatic() ? ' static' : '',
        $prop->getName(),
        $prop->isDefault() ? 'declared at compile-time' : 'created at run-time',
        var_export(Reflection::getModifierNames($prop->getModifiers()), 1)
);

// Create an instance of Str
$obj= new Str();

// Get current value
printf("---> Value is: ");
var_dump($prop->getValue($obj));

// Change value
$prop->setValue($obj, 10);
printf("---> Setting value to 10, new value is: ");
var_dump($prop->getValue($obj));

// Dump object
var_dump($obj);
?>

以上例程的输出类似于：

===> The public property 'length' (which was declared at compile-time)
     having the modifiers array (
  0 => 'public',
)
---> Value is: int(5)
---> Setting value to 10, new value is: int(10)
object(Str)#2 (1) {
  ["length"]=>
  int(10)
}

示例 #2 Getting value from private and protected properties using ReflectionProperty class

<?php

class Foo {
    public $x = 1;
    protected $y = 2;
    private $z = 3;
}

$obj = new Foo;

$prop = new ReflectionProperty('Foo', 'y');
$prop->setAccessible(true);
var_dump($prop->getValue($obj)); // int(2)

$prop = new ReflectionProperty('Foo', 'z');
$prop->setAccessible(true);
var_dump($prop->getValue($obj)); // int(2)

?>

以上例程的输出类似于：

int(2)
int(3)

参见