Page（二） Page类php 和 调用page类php

Page类php

<?php

class Page

{

    //总条数

    protected $total;

    //总页数

    protected $pageTotal;

    //每页显示数

    protected $num;

    //当前页

    protected $page;

    //超链接

    protected $url;

    //偏移量

    protected $offset;

    //初始化成员属性

    public function __construct($total , $num = 3)

    {

        $this->total = ($total < 1) ? 1 : $total;

        $this->num = $num;

        //处理总页数

        $this->pageTotal = $this->getPageTotal();

        //求出来当前页

        $this->page = $this->getPage();

        //处理偏移量

        $this->offset = $this->getOffset();

        //处理url

        $this->url = $this->getUrl();

    }

    //设置url

    //http://localhost/1606/5/page.php?name=likun

    protected function setUrl($page)

    {

        if (strstr($this->url , '?')) {

            return $this->url . '&page=' . $page;

        } else {

            return $this->url . '?page=' . $page;

        }

    }

    //处理首页

    protected function first()

    {

        return $this->setUrl(1);

    }

    //处理最后一页

    protected function last()

    {

        return $this->setUrl($this->pageTotal);

    }

    //上一页

    protected function prev()

    {

        $page = (($this->page - 1) < 1) ? 1 : $this->page - 1;

        return $this->setUrl($page);

    }

    //下一页

    protected function next()

    {

        $page = ($this->page + 1) > $this->pageTotal ? $this->pageTotal : $this->page + 1;

        return $this->setUrl($page);

    }

    //处理url

    protected function getUrl()

    {

        //return $_SERVER;

        //获取文件地址

        $path = $_SERVER['SCRIPT_NAME'];

        //获取主机名

        $host = $_SERVER['SERVER_NAME'];

        //获取端口号

        $port = $_SERVER['SERVER_PORT'];

        //获取协议

        $scheme = $_SERVER['REQUEST_SCHEME'];

        //获取网页的请求参数

        $queryString = $_SERVER['QUERY_STRING'];

        //var_dump($queryString);

        if (strlen($queryString)) {

            parse_str($queryString , $array);

            //var_dump($array);

            unset($array['page']);

            //var_dump($array);

            $path = $path . '?' . http_build_query($array);

            //var_dump($path);

        }

        $url = $scheme . '://' . $host . ':' . $port . $path;

        return $url;

    }

    //处理偏移量

    public function getOffset()

    {

        $start = ($this->page - 1) * $this->num;

        return 'LIMIT ' . $start . ',' . $this->num;

    }

    //求出来当前页

    protected function getPage()

    {

        return isset($_GET['page']) ? $_GET['page'] : 1;

    }

    //处理总页数

    protected function getPageTotal()

    {

        return ceil($this->total / $this->num);

    }

    //渲染

    public function render()

    {

        return [

            'first' => $this->first(),

            'last' => $this->last(),

            'prev' => $this->prev(),

            'next' => $this->next()

        ];

    }

}

$page = new Page(50);

调用page类php

<?php

include 'page.php';

$link = mysqli_connect('localhost' , 'root' , 'kungezuishuai');

mysqli_set_charset($link , 'utf8');

mysqli_select_db($link , 'bbs');

$sql = 'select count(*) as count from bbs_user';

$aRes = mysqli_query($link , $sql);

$count = mysqli_fetch_assoc($aRes);

$page = new Page($count['count'] , 2);

$sql2 = 'select * from bbs_user ' . $page->getOffset();

$res = mysqli_query($link , $sql2);

echo '<table width="500" border="1">';

while ($rows = mysqli_fetch_assoc($res)) {

            echo '<tr>';

                echo '<td>'.$rows['id'].'</td>';

                echo '<td>'.$rows['username'].'</td>';

                echo '<td>'.$rows['email'].'</td>';

                echo '<td>'.date('Y-m-d H:i:s' , $rows['ctime']).'</td>';

            echo '</tr>';

}

echo '</table>';

$content = $page->render();

//var_dump($content);

echo '<a href="'.$content['first'].'">首页</a>';

echo '<a href="'.$content['prev'].'">上一页</a>';

echo '<a href="'.$content['next'].'">下一页</a>';

echo '<a href="'.$content['last'].'">尾页</a>';