第二章（面向对象oop）《php和mysql web开发》《php与mysql程序设计》齐读

< ?phpclass Employee{    private $name;  //属性    private $title;    protected $wage;    protected function clockIn() { //方法        echo "Member $this->$name clocked in at ".date("h:i:s");    }    protected function clockOut() {        echo "Member $this->$name clocked out at ".date("h:i:s");    }}?>

< ?php$employee = new Employee();?>

< ?phpclass Employee{    private $name;  //声明属性的有private，public，protected    private $title;    protected $wage;}?>

< ?phpclass aa{    public $name = 'a';    function test() {        $this->name = $name; //this表示引用当前类    }}?>

< ?phpclass aa{    private $name;    public function setName($name) { //通过了公共方法来设置私有属性        $this->name = $name;    }}$b = new aa;$b->setName("Mary");?>

< ?phpclass Employee{    var $name;    function __set($propName,$propValue){//__set方法有参数属性名和值，所以这里有2个变量        echo $propName."\n";    }}$employee = new Employee();$employee->name = "Mario"; //当触发修改属性的时候，就会触发__set方法，因为这里属性只有name而没有title，所以$employee->title = "hello";?>-----title //__set执行成功的话会返回true，失败就返回false，并且会执行函数内的代码，所以这里因为没有title属性，所以失败了，并且输出了失败的title属性。

< ?php    class Employee{        private $name;        public function getName(){            return $this->name;        }        public function setName($name){            $this->name = $name;        }    }?>

< ?phpabstract class Employee{    abstract function hire();    abstract function fire();}?>

< ?phpclass mathFunctions{    const PI = '3.1415926';}echo mathFuctions::PI;  ?>

< ?php    class Book{        private $title;        private $isbn;        private $copies;        function __construct($isbn) { //这个就是构造函数            $this->setIsbn($isbn); //这里自动读取参数，设置书编码            $this->getTitle(); //自动获取书title            $this->getNumberCopies(); //自动获取有多少本相同的书        }        public function setIsbn($isbn) {            $this->isbn = $isbn;  //将参数赋值到类的属性isbn        }        public function getTitle() {            $this->title = "hello,im a title!";            print ("Title: {$this->title}"."\n");        }        public function getNumberCopies() {            $this->copies = "5";            print ("Number copies available: {$this->copies}"."\n");        }    }    $book = new Book("061452424");?>----Title: hello,im a title!    //直接实例就能够有输出，自动的。Number copies available: 5

< ?php    class Employee{        protected $name;        protected $title;        function __construct() {            echo "Employee constructor called!"."\n";        }    }    class Manager extends Employee{        function __construct() {            parent::__construct(); //实例Manager对象就能够执行了Employee对象的构造函数            echo "Manager constructor call!"."\n";        }    }    $employee = new Manager();?>----Employee constructor called!Manager constructor call!

例如：classname::__constructor();

< ?php    class Employee{        protected $name;        protected $title;        function __construct() {            echo "Employee constructor called!"."\n";        }        function __destruct() {            echo "Its destroyed!"."\n";        }    }    $employee = new Employee();?>----Employee constructor called!Its destroyed! //脚本执行结束就会撤销内存中的对象。

< ?phpclass Visitor{    private static $visitor = 0;  //设置了静态属性    function __construct() {        self::$visitor++; //静态属性和方法需要使用self来引用    }    static function getVistors() {  //设置了静态方法，其实这里不用static也可以，静态方法是可以不用实例化而直接调用的，这里因为构造函数实例化了，所以用不用static function都可以        return self::$visitor;    }}$visits = new Visitor();echo $visits::getVistors()."\n"; //静态方法需要使用::来调用$visits2 = new Visitor();echo $visits2::getVistors()."\n";?>----1   //计数没有终止，而是继续累计。2