PHP 高级课程笔记 面向对象

  例一:

  

复制代码 代码如下:

  <?php

  // 类的定义

  class User

  {

  // 属性,注意public、private、protected的作用范围

  public $name = "hackbaby";

  // 构造函数

  function __construct()

  {

  echo "construct<br />";

  }

  // 方法

  function say()

  {

  echo "这是在类的本身调用:$this->name";

  }

  // 析构函数

  function __destruct()

  {

  echo "destruct";

  }

  // 返回当前对象的描述信息 通过实例化的变量名调用例如本例中的$user

  function __toString()

  {

  return "user class";

  }

  }

  //实例化,如果构造函数有参数则用$user = new User('参数');

  $user = new User();

  echo $user->name . "<hr />";

  $user->say();

  echo "<hr />";

  echo $user;

  ?>

  例二:

  

复制代码 代码如下:

  <?php

  class Fruit

  {

  protected $fruit_color;

  protected $fruit_size;

  function setcolor($color)

  {

  $this->fruit_color = $color;

  }

  function getcolor()

  {

  return $this->fruit_color;

  }

  function setsize($size)

  {

  $this->fruit_size = $size;

  }

  function getsize()

  {

  return $this->fruit_size;

  }

  function save()

  {

  //代码

  }

  }

  class apple extends Fruit

  {

  private $variety;

  function setvariety($type)

  {

  $this->variety = $type;

  }

  function getvariety()

  {

  return $this->variety;

  }

  }

  $apple = new apple();

  echo $apple->setvariety('红富士');

  echo $apple->getvariety();

  echo "<br />";

  echo $apple->setcolor('red');

  echo $apple->getcolor();

  echo "<br />";

  echo $apple->setsize('特大');

  echo $apple->getsize();

  ?>