PHP教程
interface demo { 
const NAME = "常量對象屬性"; 
function fun1(); 
function fun2(); //抽象方法. 
} 

PHP教程
class MyPc implements demo , demo2 , demo3 { 
... 
} 

PHP教程
abstract class MyPc implements demo , demo2 , demo3 { 
... 
} 

PHP教程
class MyPc extends Root implements demo , demo2 , demo3 { 
... 
} 

PHP教程
interface demo3 extends demo { 
... 
} 

PHP教程
<?php 
interface demo { 
 const NAME = "名稱"; 
 function fun1(); 
 function fun2(); 
} 
interface demo2 { 
 function fun3(); 
 function fun4(); 
} 
interface demo3 { 
 const TEST = "Test"; 
 function fun5(); 
} 
class MyPc implements demo, demo2 { 
 function fun1() { 
 echo "++++++++++<br />"; 
 } 
 function fun2() { 
 echo "----------<br />"; 
 } 
 function fun3() { 
 echo "1111111111<br />"; 
 } 
 function fun4() { 
 echo "2222222222<br />"; 
 } 
} 
class MyPs extends MyPc implements demo3 { 
 function fun5() { 
 echo "繼承類后引用接口"; 
 } 
} 
$p = new MyPs; 
$p->fun1(); 
$p->fun2(); 
$p->fun3(); 
$p->fun4(); 
$p->fun5(); 
?> 

PHP教程
<?php 
//定義接口 
interface User{ 
 function getDiscount(); 
 function getUserType(); 
} 
//VIP用戶 接口實現 
class VipUser implements User{ 
 // VIP 用戶折扣系數 
 private $discount = 0.8; 
 function getDiscount() { 
  return $this->discount; 
 } 
 function getUserType() { 
  return "VIP用戶"; 
 } 
} 
class Goods{ 
 var $price = 100; 
 var $vc; 
 //定義 User 接口類型參數,這時并不知道是什么用戶 
 function run(User $vc){ 
  $this->vc = $vc; 
  $discount = $this->vc->getDiscount(); 
 $usertype = $this->vc->getUserType(); 
  echo $usertype."商品價格：".$this->price*$discount; 
 } 
} 
$display = new Goods(); 
$display ->run(new VipUser); //可以是更多其他用戶類型 
?> 

PHP教程
class 子類 extends 父類 implemtns 接口1, 接口2, ... 
{ 
 ...... 
} 

PHP教程
<?php
//簡單定義實現接口
interface UserInterface{ //定義user接口
 function getname();
}
interface TeacherInterface{ //定義teacher接口
 function getLengthofService();
}
class User implements UserInterface{ //實現user接口
 private $name="nostop";
 public function getName(){
  return $this->name;
 }
}
class Teacher implements TeacherInterface{ //實現teacher接口
 private $age=23;
 public function getLengthofService(){
  return $this->age;
 }
}
$user=new User();
echo $user->getName().'<br />';//nostop
$teacher=new Teacher();
echo $teacher->getLengthofService().'<br />';//23
//繼承類實現接口
class GraduResultudent extends User implements TeacherInterface{ //繼承User類 實現接口
 private $teacher;
 public function __construct(){  //定義構造函數
  $this->teacher=new Teacher(); //實例化Teacher對象
 }
 public function getLengthOfService(){ //實現TeacherInterface接口的方法
  return $this->teacher->getLengthOfService();
 }
}
class Result{
 public static function getUserName(UserInterface $_user){ //注意：這里面的類型變成接口類型
  echo "Name is ".$_user->getName().'<br />';
 }
 public static function getLengthOfService(TeacherInterface $_teacher){ //注意：這里面的類型變成接口類型
  echo "age is ".$_teacher->getLengthOfService();
 }
}
$object=new GraduResultudent();
Result::getUserName($object); //Name is nostop
Result::getLengthOfService($object); //age is 23
echo "<br />";
//接口實現用戶的折扣
interface People{ //定義接口
 function getUserType();
 function getCount();
}
class VipUser implements People{ //實現接口
 //用戶折卡系數
 private $discount=0.8;
 function getUserType(){
  return "VIP用戶";
 }
 function getCount(){
  return $this->discount;  
 }
}
$vip=new VipUser(); //實現化對象
echo $vip->getUserType().'商品價格：'.$vip->getCount()*100; //VIP用戶商品價格：80
class Goods{
 var $price=100;
 var $member;
 function run(People $member){ //注意：這里面的參數類型是接口類型
  $this->member=$member;
  $discount=$this->member->getCount();
  $usertype=$this->member->getUserType();
  echo $usertype."商品價格：".$this->price*$discount;
 }
}
$display=new Goods();
$display->run(new VipUser);//VIP用戶商品價格：80
?>