yii框架的增删改查加分页简单代码[yii 2.0]

/*传页面
 * 添加、展示到表单页面
 */
public function actionMyshow(){
   return $this->render('add');
}
/*增
 * 添加接值、判断添加成功或失败
 */
public function actionAdd_do(){
    $data = $_POST;
    $yy = Yii::$app->db->createCommand()->insert('user',$data)->execute();
    if($yy){
        echo "<script>alert('添加成功')</script>";
        $this->redirect('index.php?r=myshow/show');
    }else{
        echo "<script>alert('添加失败')</script>";
        $this->redirect('index.php?r=myshow/add');
    }
}

/*查
 * 展示页面、查询
 */
public function actionShow()
{
    $db = yii::$app->db;
    $sql = "select * from user";
    $data = $db->createCommand($sql)->queryAll();

    $p = empty($_GET['page']) ? 1 : $_GET['page'];
    $num = count($data);//总条数
    $size = 2;//每页显示条数
    $end = ceil($num / $size);//尾页
    $prev = $p - 1 < 1 ? $p : $p - 1;//上一页
    $next = $p + 1 >= $end ? $end : $p + 1;//下一页
    $offset = ($p - 1) * $size;//偏移量
    $sql = "select * from user limit $offset,$size";//分页查询
    $arr = $db->createCommand($sql)->queryAll();
    return $this->render('show', ['data' => $arr,'end'=>$end,'prev'=>$prev,'next'=>$next]);
}

/*删
 * 删除、判断删除成功或失败
 */

public function actionDelete(){
    /*删除表单页面接收当前条的id
     * <a href="index.php?r=myshow/delete&id=<?php echo $v['id']?>">删除</a>
     */
    $request = \Yii::$app->request;
    $id = $request->get('id');
    $res = \Yii::$app->db->createCommand()->delete('user', "id = $id")->execute();
    if($res){
        echo "<script>alert('删除成功')</script>";
        $this->redirect('index.php?r=myshow/show');
    }else{
        echo "<script>alert('删除失败')</script>";
        $this->redirect('index.php?r=myshow/show');
    }
}

 public function actionUpdate(){
        $request = \Yii::$app->request;
        $id = $request->get('id');
        $command = \Yii::$app->db->createCommand("SELECT * FROM user WHERE id=$id");
        $post = $command->queryOne();
        return $this->render('update',['list'=>$post]);
        //表单页面接到值展示如下：
        /*
         * <tr>
                    <td>姓名</td>
                    <td><input type="text" name="name" value="<?php echo $list['name']?>"/></td>
                </tr>
         */

    }

    /*
     * 修改数据判断修改成功或失败
     */
    public function actionUpdate_do(){
        $id=$_POST['id'];
        $data = $_POST;
        $res = \Yii::$app->db->createCommand()->update('user',$data,["id" => $id])->execute();
        if($res){
            echo "<script>alert('修改成功')</script>";
            $this->redirect('index.php?r=myshow/show');
        }else{
            echo "<script>alert('修改失败')</script>";
            $this->redirect('index.php?r=myshow/show');
        }
    }