检查属性是否存在

Question

是否可以检查是否存在使用魔术设定器设置的属性？

class Test
{
    private $vars;

    public function __set($key, $value) {
        $this->vars[$key] = $value;
    }

    public function &__get($key)
    {
        return $this->vars[$key];
    }
}

$test = new Test;

$test->myvar = 'yay!';

if (magic_isset($test->myvar)) {
}

或者不可能,我只需要在班上设置另一个功能？

Answer 1

使用__isset()和isset():

public function __isset($key)
{
    return isset($this->vars[$key]);
}

$test = new Test;

$test->myvar = 'yay!';

if (isset($test->myvar)) {

}