12月03日类与对象复习-九期线上班

手抄笔记

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练习案例

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demo1:

<?php
        //创建类
        class Demo1{
            //添加类成员
            //属性
            public $name = '33703259';
            //方法
            public function GET(){
                $obj = new Demo1();
                return '名称：' . $obj->name . '<hr>';
            }
        }
        //访问类成员
        $obj =new Demo1();
        echo $obj->GET();
        echo $obj->name;

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demo2:

<?php
//创建类
class Demo2{
    //添加类成员
    public $name = 'WJF';
    public $qq = '33703259';
    public function getname(){
//        self当前类名
        $obj = new self();
        return '用户名：' . $obj->name . '<hr>';
    }
    public function getqq(){
//        $this 当前类的实例引用
        return 'QQ:' . $this->qq;
    }
}
//访问类成员
    $obj = new Demo2();
    echo $obj->getname();
    echo $obj->getqq();

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demo3:

<?php
    class Demo3{
        public $name;
        public $qq;
        public function get(){
            return  '用户名：' . $this->name . 'QQ:'  . $this->qq;
        }
        public function __construct($name,$qq)
        {
            $this->name = $name;
            $this->qq = $qq;
            echo $this->get();
        }
    }
        new Demo3('用户名','QQ');

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demo4:

<?php
//创建类
class d4{
    //添加类成员
    public $name;
    protected $qq;
    public function get(){
        return '用户名：' . $this->name .'QQ:' . $this->qq;
    }
//    构造方法
    public function __construct($name,$qq)
    {
        $this->name = $name;
        $this->qq = $qq;
    }
    //魔术方法 __get($name),属性重载
    public function __get($name)
    {
        $id = $_GET['id'] ?? '';
        if (isset($id) and $id==='1'){
            return isset($this->qq) ? $this->qq : '当前暂无该用户QQ';
        }else{
            return '您不符合当前操作权限要求';
        }
    }
}
//访问类成员
    $obj = new d4('wjf','33703259');
    echo $obj->qq;

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demo5:

<?php
    //类的继承
    class d5{
        public $name;
        public $qq;
        public function get(){
            return '用户名：' . $this->name .'QQ:' . $this->qq;
        }
        //    构造方法
        public function __construct($name,$qq)
        {
            $this->name = $name;
            $this->qq = $qq;
        }
    }
    class d5_1 extends d5{
        private $zt;
        public function __construct($name, $qq,$zt)
        {
            parent::__construct($name, $qq);
            $this->zt = $zt;
        }
        public function get()
        {
            return parent::get() . '状态：' . $this->zt;
        }
    }
    $obj = new d5_1('WJF','33703259','在线');
    echo $obj->get();

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demo6:

<?php
    //trait:代码复用
    trait T{
        public function get(){
            return '用户名：' . $this->name .'QQ:' . $this->qq;
        }
    }
    class d6{
        use T;
        public $name;
        public $qq;
        public function __construct($name,$qq)
        {
            $this->name = $name;
            $this->qq = $qq;
        }
    }
class d6_1 extends d6{
    private $zt;
    public function __construct($name, $qq,$zt)
    {
        parent::__construct($name, $qq);
        $this->zt = $zt;
    }
    public function get()
    {
        return parent::get() . '状态：' . $this->zt;
    }
}
$obj = new d6_1('WJF','33703259','离线');
echo $obj->get();

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demo7:

<?php
    //接口
    interface idemo{
        public function get();
    }
class d7 implements idemo{
    public $name;
    public $qq;
    public function get(){
        return '用户名：' . $this->name .'QQ:' . $this->qq;
    }
    public function __construct($name,$qq)
    {
        $this->name = $name;
        $this->qq = $qq;
    }
}
$obj = new d7('WJF','33703259');
echo $obj->get();

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demo8:

<?php
    //抽象类
    abstract class cx{
        //抽象方法
        abstract public function get();
        //已实现的方法
        public function h(){
            return '已实现方法';
        }
    }
class d8 extends cx {
    public $name;
    public $qq;
    public function get(){
        return '用户名：' . $this->name .'QQ:' . $this->qq;
    }
    public function __construct($name,$qq)
    {
        $this->name = $name;
        $this->qq = $qq;
    }
}
$obj = new d8('WJF','33703259');
echo $obj->get();
echo $obj->h();