MYSQL 数据库内容的分页展示

 <button id=‘show‘>查询</button>
 <div class="div"></div>

 // 默认
        $(‘#show‘).on(‘click‘, function () {
            var numb = 1;
            var type = ‘show‘;
            $.ajax({
                type: ‘post‘,
                url: ‘php/page.php‘,
                data: {
                    ‘p‘: numb,
                    ‘type‘: type
                },
                success: function (msg) {
                    $(‘.div‘).html(msg)
                }
            })
        })
        function page(num) {
            var numb = num.value;
            var type = ‘page‘
            $.ajax({
                type: ‘post‘,
                url: ‘php/page.php‘,
                data: {
                    ‘p‘: numb,
                    ‘type‘: type
                },
                success: function (msg) {
                    $(‘.div‘).html(msg);
                }
            })
            console.log(numb);
        }

 // 根据表名获取数据 当前表一共有多少条记录
    // 这里可以把表名作为参数 也可以直接写在方法内
    // 根据表名获取数据总数
    protected function getTableNum($tbname)
    {
        $sql = "SELECT COUNT(*) FROM `{$tbname}`;";
        $res = $this->db->query($sql)->fetch_assoc()["COUNT(*)"];
        return $res;
    }
    // * 功能：获得分页数量
    // * @parm string $tbname
    // * @reurn int $PageNum
    // */
    function getPageNum($tbname, $pageNum = 5)
    {
        $dataNum = $this->getTableNum($tbname);
        $Num = ceil($dataNum / $pageNum);
        return (int) $Num;
    }
    // //根据pid获取分页
    public function page($pid, $pageNum = 5)
    {
        $pid = ($pid - 1) * $pageNum;
        $sql = "SELECT * FROM `main` LIMIT {$pid},{$pageNum};";
        $res = $this->db->query($sql)->fetch_all(MYSQLI_ASSOC);
        return $res;
    }

$type = $_REQUEST[‘type‘];
// 显示第一页
if ($type == ‘show‘) {
    $pid = $_REQUEST[‘p‘];
    $tbname = ‘main‘;
    $res = $db->page($pid, $pageNum = 5);
    $str = "<table>";
    foreach ($res as $key => $value) {
        $str .= "<tr>";
        foreach ($value as $k => $v) {
            $str .= "<td style=‘border:1px solid grey‘>{$v}</td>";
        }
        $str .= "</tr>";
    }
    $str .= "</table>";
    echo $str;
    // 按钮部分
    $num = $db->getPageNum($tbname, $pageNum = 5);
    if ($pid > 1) {
        $back = $pid * 1 - 1;
    } else {
        $back = $pid;
    }
    if ($pid < $num) {
        $next = $pid * 1 + 1;
    } else {
        $next = $pid;
    }
    $jump = "<button value=‘{$back}‘ onclick=‘page(this)‘>上一页</button>";
    for ($i = 1; $i <= $num; $i++) {
        $jump .= "<button style=‘color:red‘ value=‘{$i}‘onclick=‘page(this)‘ >$i</button>";
    }

    $jump .= "<button value=‘{$next}‘ onclick=‘page(this)‘>下一页</button>";
    echo $jump;
}
// 显示其他页面
if ($type == ‘page‘) {
    $pid = $_REQUEST[‘p‘];
    $back = $pid * 1 - 1;
    $next = $pid * 1 + 1;
    $tbname = ‘main‘;
    $res = $db->page($pid, $pageNum = 5);
    $str = "<table>";
    foreach ($res as $key => $value) {
        $str .= "<tr>";
        foreach ($value as $k => $v) {
            $str .= "<td style=‘border:1px solid grey‘>{$v}</td>";
        }
        $str .= "</tr>";
    }
    $str .= "</table>";
    echo $str;
    // 按钮部分
    $num = $db->getPageNum($tbname, $pageNum = 5);
    if ($pid > 1) {
        $back = $pid * 1 - 1;
    } else {
        $back = $pid;
    }
    if ($pid < $num) {
        $next = $pid * 1 + 1;
    } else {
        $next = $pid;
    }
    $jump = "<button value=‘{$back}‘ onclick=‘page(this)‘>上一页</button>";
    for ($i = 1; $i <= $num; $i++) {
        $jump .= "<button style=‘color:red‘ value=‘{$i}‘ onclick=‘page(this)‘ >{$i}</button>";
    }

    $jump .= "<button value=‘{$next}‘ onclick=‘page(this)‘>下一页</button>";
    echo $jump;