<?php

class UserName
 { 
//定义属性    
     private $name;

//定义构造函数
     function __construct( $name )
     {
          $this->name = $name; //这里已经使用了this指针
     }

//析构函数
     function __destruct(){}

//打印用户名成员函数
     function printName()
     {
          print( $this->name ); //又使用了this指针
     }
 }

//实例化对象
 $nameObject = new UserName( "heiyeluren" );

//执行打印
 $nameObject->printName(); //输出: heiyeluren

//第二次实例化对象
 $nameObject = new UserName( "PHP" );

//执行打印
 $nameObject->printName(); //输出：PHP
 ?> 

<?php

class Counter
     {
//定义属性，包括一个静态变量
         private static $firstCount = ;
private $lastCount;

//构造函数
         function __construct()
         {
              $this->lastCount = ++selft::$firstCount;

　　　　　　　  //使用self来调用静态变量,使用self调用必须使用::(域运算符号)
         }

//打印最次数值
         function printLastCount()
         {
              print( $this->lastCount );
         } 
     }

//实例化对象
 $countObject = new Counter();

 $countObject->printLastCount(); //输出 

?> 

<?php

//基类
 class Animal
 {
//基类的属性
     public $name; //名字

//基类的构造函数
     public function __construct( $name )
     {
          $this->name = $name;
     }
 }

//派生类
 class Person extends Animal //Person类继承了Animal类
 {
public $personSex; //性别
     public $personAge; //年龄

//继承类的构造函数
     function __construct( $personSex, $personAge )
     {
          parent::__construct( "heiyeluren" ); //使用parent调用了父类的构造函数
          $this->personSex = $personSex;
          $this->personAge = $personAge;
     }

     function printPerson()
     {
          print( $this->name. " is " .$this->personSex. ",this year " .$this->personAge );
      }
 }

//实例化Person对象
 $personObject = new Person( "male", "");

//执行打印
 $personObject->printPerson(); //输出：heiyeluren is male,this year 

?>