//类的作用域final:将阻止子类重写这个字段 //方法的作用域abstract: 在父类中声明，在子类中实现 //定义类： class Employee{ //定义字段 private $name; protected $title; public $wage; //常量 const PI = 3.1415926; //静态成员变量 private static $visitors = 0; //定义构造函数 function __construct(){ //使用静态成员变量 self::$visitors++; echo "constructor"; } //定义析构函数 function __destruct(){ echo "destruct"; } //声明方法 public function clockIn(){ //使用字段 echo "Member $this->name"; } //在访问一个对象并不拥有的属性时(比如私有字段)，如果该对象用户__get和__set方法，则会自动调用__get方法或__set方法 function __set($property,$value){ $this->$property = $value; } function __get($property){ return $this->$property; } } //类的继承 Manager继承Employee class Manager extends Employee { function __construct(){ //调用父类的构造函数或方法 parent::__construct(); parent::clockIn(); echo "Manager constructor"; } } //创建对象 $employee = new Employee(); $employee->wage = 10000; //使用常量 echo Employee::PI; //调用方法 $employee->clockIn(); $manager = new Employee(); //instanceof判断一个对象是类的实例、类的子类，还是实现了某个特定接口 if($manager instanceof Employee ) echo "Yes";

//对象克隆 class ClassA{ private $name; private $title; public function setName($name){ $this->name = $name; } function getName(){ return $this->name; } public function setTitle($title){ $this->title = $title; } public function getTitle(){ return $this->title; } function __clone(){ echo "我被克隆了","<br>"; } } $classA = new ClassA(); $classA->setName("NameA"); $classA->setTitle("TitleA"); $classB = clone $classA; $classB->setName("NameB"); echo $classA->getName(),"<br>",$classA->getTitle(),"<br>"; echo $classB->getName(),"<br>",$classB->getTitle(),"<br>"; /* output 我被克隆了 NameA TitleA NameB TitleA */

//接口 interface IPillage{ function method(); } class ClassC extends ClassA implements IPillage { function method(){ echo "inteface method"; } } $classC = new ClassC(); $classC->method(); //inteface method

//抽象类，是不能实例化的类，只能作为其它类继承的基类 abstract class BaseClass{ protected $name; abstract function method(); } class ChileClass extends BaseClass { function method(){ echo "method"; } } $child = new ChileClass(); $child->method(); //output method