php开发之接口的使用

继承简化了对象，类的创建，增加了代码的可重性，但php只支持单继承，如果要实现多重继承，就要使用多个接口。
接口通过interface关键字来声明，并且类中只能包含未实现的方法和一些成员变量，格式如下：
interface interfaceName{
function interfaceName1();
function interfaceName2();
…
}

子类是通过implements关键字来实现接口的，如果要实现多个接口，那么每个接口之间应使用逗号“，”连接。而且所有未实现的方法都要在子类中实现，否则php将出错。格式如下：
class SubClass implments interfaceName1,interfaceName2{
function interfaceName1(){
//功能实现
}
function interfaceName2(){
//功能实现
}

}

示例代码如下：

<code><span><span><span><?php </span><span>//声明接口A</span><span><span>interface</span><span>A</span>{</span><span><span>function</span><span>Aa</span><span>()</span>;</span>
}
  <span>//声明接口B</span><span><span>interface</span><span>B</span>{</span><span><span>function</span><span>Bb</span><span>()</span>;</span>
}

 <span><span>class</span><span>Am</span><span>implements</span><span>A</span>{</span><span><span>function</span><span>Aa</span><span>()</span>{</span><span>echo</span><span>"Aa is a php coder"</span>;
    }
 }

 <span><span>class</span><span>Bm</span><span>implements</span><span>A</span>,<span>B</span>{</span><span><span>function</span><span>Aa</span><span>()</span>{</span><span>echo</span><span>"Mike is a php coder<br>"</span>;
    <span>echo</span><span>"Mike is an ios coder<br>"</span>;
    }

    <span><span>function</span><span>Bb</span><span>()</span>{</span><span>echo</span><span>"Jack is a java coder"</span>;
    }
 }

 <span>$jack</span> =<span>new</span> Am();
 <span>$bluce</span> =<span>new</span> Bm();

 <span>$jack</span>->Aa();
 <span>echo</span><span>"<br>"</span>;
 <span>$bluce</span>->Aa();
 <span>$bluce</span>->Bb();

<span>?></span></span></span></span></code>

运行结果如下：

以上就介绍了php开发之接口的使用，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。