php：对象继承和多态的实例

<?php

	/*父类*/
	class MyObject{
		
		public $object_name;								//名称
		public $object_price;								//价格
		public $object_num;									//数量
		public $object_agio;								//折扣
		
		function construct($name,$price,$num,$agio){
			
			$this -> object_name = $name;
			$this -> object_price = $price;
			$this -> object_num = $num;
			$this -> object_agio = $agio;
			
			
		}
		
		function showMe(){
			echo '这句话不会显示。';
		}
		
	}
	/*  子类Book  */
	class Book extends MyObject{
		
		public $book_type;									//类别
		
		function construct($type,$num){
			
			$this -> book_type = $type;
			$this -> object_num = $num;
		}
		
		function showMe(){
			
			return '本次新进'.$this -> book_type.'图书'.$this -> object_num.'<br>';
		}
	}
	/*  子类Elec  */
	class Elec extends MyObject{
	
		function showMe(){
			
			return '热卖商品'.$this -> object_name.'<br>原价：'.$this -> object_price.'<br>特价：'.$this -> object_agio * $this -> object_price;
		}
	}
	/*	实例化对象	*/
	$c_book = new Book('计算机类',1000);
	$h_elec = new Elec('待机王XX手机',1200,3,0.8);
	echo $c_book->showMe()."<br>";
	echo $h_elec->showMe();
	
	
?>