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复制代码 代码如下:


    /**php语言是支持面向对象编程的,对于面向对象的编程,学过java和C++的人都知道啊!
      *如果不清楚的去baidu问一下就可以了。
    */   

    //我们来定义一个类,定义类的关键字是 “class”   
    class computer {

        //在类里面可以创建方法,变量等

        //定义一个加法
        function add ($n1,$n2) {

            $sum = $n1 + $n2;
            return $sum;
        }       
        //定义一个减法
        function jf ($n1,$n2) {

            $sum = $n1 - $n2;
            return $sum;   
        }       
        //定义一个乘法
        function cf ($n1,$n2) {           

            $sum = $n1 * $n2;
            return $sum;   
        }               
    }

    /**
    如何使用类中的方法,就要创建类的对象,用对象调用方法
    下面是调用类的方法
    */

    //$com 就是computer类的对象,创建对象用new关键字
    $com = new computer();

    //调用类中的方法就用  对象名 -> 方法名(参数,参数...)
    echo $com -> add(1,2);
    echo $com -> jf(1,2);
    echo $com -> cf(1,2);

    //这些方法被按钮调用的化,就可以简单编写出一个计算器来,
    //每个按钮对应一个方法
?>
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