[PHP面向对象]①④--__isset/__unset/empty

<?php

class MagicTest
{

    public function __get($name)
    {
        return "Getting the property " . $name . "<br/>";
    }

    public function __set($name, $value)
    {
        echo "Setting the property " . $name . " to value " . $value . "<br/>";
    }

    public function __isset($name)
    {
        echo "__isset invoked" . "<br/>";
        return false;
    }

    public function __unset($name)
    {
        echo "unsetting property " . $name . "<br/>";
    }
}

$obj = new MagicTest();
echo $obj->className . "<br/>";//Getting the property className
$obj->className = 'MagicClassX';//Setting the property className to value MagicClassX

echo '$obj->className is set?' . isset($obj->className) . "<br/>";
//__isset invoked
//$obj->className is set?1
echo 'obj->className is empty? ' . empty($obj->className) . "<br/>";//__isset return false 为1
unset($obj->className);//unsetting property className

?>

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