PHP手册中property_exists的范例是不是出错了？? 400 报错

Note that before PHP 5.3.3, this function fails for private properties in base classes (which is fixed in 5.3.3)

<?php class Base { private $var = 1;

    public function test() {
            var_dump( property_exists( $this, 'var' ) );
    }

}

class Derived extends Base { }

$b = new Base(); $b->test(); $d = new Derived(); $d->test(); ?>

Executing this code with PHP 5.0 <= x < 5.3 this script echoes (incorrect result):
bool(true)
bool(false)

Executing this code with PHP 5.3 this script echoes (correct result):
 bool(true)
 bool(true)

 在php5.3.3中已经修复了这个问题。你的例子的测试结果是在5.3.3版本之前得出的，所以有一定的出入。在php5.3.3中得出全部ture的结果是正常的。

引自:http://cn2.php.net/property_exists

<?php
class Base {
        private $var = 1;

        public function test() {
                var_dump( property_exists( $this, 'var' ) );
        }
}

class Derived extends Base {
}

$b = new Base();
$b->test();
$d = new Derived();
$d->test();
?>