第七节--类的静态成员 -- Classes and Objects in PHP5 [7]

<?php    class Counter    {        private static $count = 0;        const VERSION = 2.0;        function __construct()        {            self::$count++;        }        function __destruct()        {            self::$count--;        }        static function getCount()        {            return self::$count;        }    };    //创建一个实例,则__construct()将执行    $c = new Counter();    //输出 1    print(Counter::getCount() . "<br>n");    //输出类的版本属性    print("Version used: " . Counter::VERSION . "<br>n"); ?>