PHP - Manual: ReflectionProperty::hasDefaultValue
2024-12-23
(PHP 8)
ReflectionProperty::hasDefaultValue — Checks if property has a default value declared
Checks whether the property was declared with a default value, including an implicit
null
default value. Only returns false
for typed properties without default value (or
dynamic properties).
此函数没有参数。
If the property has any default value (including null
) true
is returned;
if the property is typed without a default value declared or is a dynamic property, false
is returned.
示例 #1 ReflectionProperty::hasDefaultValue() example
<?php
class Foo {
public $bar;
public ?int $baz;
public ?int $foo = null;
public int $boing;
public function __construct()
{
$this->ping = '';
}
}
$ro = new ReflectionObject(new Foo());
var_dump($ro->getProperty('bar')->hasDefaultValue());
var_dump($ro->getProperty('baz')->hasDefaultValue());
var_dump($ro->getProperty('foo')->hasDefaultValue());
var_dump($ro->getProperty('boing')->hasDefaultValue());
var_dump($ro->getProperty('ping')->hasDefaultValue()); // Dynamic property
var_dump($ro->getProperty('pong')->hasDefaultValue()); // Not defined property
?>
以上例程会输出:
bool(true) bool(false) bool(true) bool(false) bool(false) Fatal error: Uncaught ReflectionException: Property Foo::$pong does not exist in example.php
官方地址:https://www.php.net/manual/en/reflectionproperty.hasdefaultvalue.php