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将数据填充到前端的代码表格中

<?php
namespace _0819;
// 将数据填充到前端的代码表格中
// fetch + while
// fetchALL+ foreach
// bindValue 值绑定到变量上
// bindParam  引用绑定到变量上
// bindColumn  将字段绑定到变量上
// 'SELECT `id`,`name`,`email` FROM `staff`';
use PDO;
$db = new PDO('mysql:dbname=bittel','root','root');
//   herdoc
$sql =  <<<   SQL
    SELECT `id`,`name`,`sex`,`email`
        FROM `staff`;
SQL;
// sql语句对象预处理
$stmt = $db->prepare($sql);
// 执行sql
$stmt->execute();
// while,foreach, list()进行结果数组的解构到变量中
// 0  1 2 3 替换 bindColumn里面第一个数的值
$stmt->bindColumn('id', $id);
$stmt->bindColumn('name', $name);
$stmt->bindColumn('sex', $sex);
$stmt->bindColumn('email', $email);
// 此种展示太简单 不会用的
// while ($stmt->fetch() ){
// printf('%d:%s,%d,(%s)<br>',$id,$name,$sex,$email);
// }
// 此次以表格方式展示
$table =<<<TABLE
<style>
table {
border-collapse: collapse;
width: 90%;
min-width: 360px;
margin: 30px auto;
text-align:center;
}
table,th,td {
border: 1px solid #000;
padding: 5px;
}
table caption {
font-size: 18px;
margin-bottom: 10px;
}
table thead {
background: lightcyan;
}
table tbody tr:hover {
cursor: pointer;
background: #efefef;
}
</style>
<table>
<caption>员工信息表</caption>
<thead>
    <tr>
        <th>ID</th>
        <th>姓名</th>
        <th>性别</th>
        <th>邮箱</th>
    </tr>
</thead>
<tbody>
TABLE;
// while ($stmt->fetch() ){
// printf('%d:%s,%d,(%s)<br>',$id,$name,$sex,$email);
// }
while ($stmt->fetch(PDO::FETCH_BOUND) ){
    // 对性别进行处理  0 、1
   $tsex= $sex?'男':'女';
// 拼装 html 代码
$table .= <<<TR
<tr>
<td>$id</td>
<td>$name</td>
<td>$tsex</td>
<td>$email</td>
</tr>
TR;
}
$table .='</tbody></table>';
echo $table;

获取分页数据

<?php
// 获取分页数据
namespace _0819;
use PDO;
// 连接 
$db = new PDO('mysql:dbname=bittel','root','root');
// 1、页数
$page = $_GET['p'];
echo '当前页数，p：'.$page.'<br>';
// 2、每页展示的数据 num =5
$num =5 ;
echo '当前数量：num'.$num.'<hr>';
// 3、偏移量  offset = (页数 -1)*数量
$offset =($page - 1) * $num;
// 打印当前偏移量
echo '当前偏移量 offse:'.$offset.'<hr>';
// $sql = <<< SQL
$sql = <<< SQL
    SELECT *
    FROM `staff`
    LIMIT $offset, $num;
SQL;
$stmt = $db ->prepare($sql);
$stmt->execute();
$staffs = $stmt ->fetchAll(PDO::FETCH_ASSOC);
// fetchAll 是二维数组
foreach($staffs as $staff){
// list($id,$name,....) 简化extract()   解构后得到一系类变量
extract($staff) ;
printf('%d-%s-%s-%s<br>', $id, $name, $sex, $email);
}

获取总页数

<?php
// 获取总页数
namespace _0819;
use PDO;
// 连接 
$db = new PDO('mysql:dbname=bittel','root','root');
// 1、页数   必须要给一个默认页数值，。不然报错  用两个？？赋值
$page = $_GET['p']??1;
echo '当前页数，p：'.$page.'<br>';
// 2、每页展示的数据 num =5
$num =5 ;
echo '当前数量：num'.$num.'<hr>';
// 3、偏移量  offset = (页数 -1)*数量
$offset =($page - 1) * $num;
// 打印当前偏移量
echo '当前偏移量 offset:'.$offset.'<hr>';
// 4、计算总记录数
//方式一： SELECT COUNT('id')  FROM `staff`;
// 方式二：SELECT COUNT(*)  AS `total`  FROM   `staff`;  起别名
// 计算页数 一步到位：SELECT CEIL( COUNT(*)/5)  AS `total`  FROM   `staff`;
// 推荐
  $sql ='     SELECT COUNT(*)  AS `total`  FROM   `staff`;' ; 
  $stmt = $db ->prepare($sql);
  $stmt->execute();
// 将总数量绑定到一个变量上
$stmt ->bindColumn('total',$total);
$stmt->fetch();
echo'当前的总记录数：$total:'.$total.'<hr>';
// 5. 计算总页数
// 向上取整
$pages = ceil($total / $num);
echo '当前总页数: pages = ' . $pages . '<hr>';
$sql = <<< SQL
    SELECT *
    FROM `staff`
    LIMIT $offset, $num;
SQL;
$stmt = $db->prepare($sql);
$stmt->execute();
$staffs = $stmt->fetchAll(PDO::FETCH_ASSOC);
// 在foreach遍历前增加判断是否存在数据
if(count($staffs)===0){
    echo '查询结果为空';
}else{
    foreach($staffs as $staff){
        extract($staff);
        printf('%d--%s---%s----%s<br>',$id,$name,$sex,$email);
    }
}
function createPages(int $page, int $pages): array
{
    // 当前是第8页, 共计20页
    // [1,  ...    6, 7, 8, 9, 10,  ....    20]
    // 当前是第10页, 共计20页
    // [1,  ...    8, 9, 10, 11, 12,  ....    20]
    // 1. 生成与总页数长度相同的递增的整数数组
    $pageArr = range(1, $pages);
    // 2. 只需要当前和前后二页, 其它页码用 false/null 来标记
    $paginate =  array_map(function ($p) use ($page, $pages) {
        return   ($p == 1 || $p == $pages || abs($page-$p) <=2) ? $p : '...';
    }, $pageArr);
    // dump($paginate);
    // 去重, 替换
    $before = array_unique(array_slice($paginate, 0, $page));
    $after = array_unique(array_slice($paginate, $page));
    // 用解构进行合并
    return [...$before, ...$after];
}
echo '<hr>';
$pgnull = createPages($page, $pages);
print_r($pgnull);
// array_map ($pgnull as $pg ){
//     if ( $pg===null){
//          return '...';
//     }else {
//         return $pg;
//     }
//  }

分页展示数据

<?php
// 加载zuoye3.php
require 'zuoye3.php';
echo'<hr>';
?>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>分页展示数据</title>
    <style>
        table {
            width: 400px;
            border-collapse: collapse;
            text-align: center;
        }
        table th,
        table td {
            border: 1px solid;
            padding: 5px;
        }
        table thead {
            background-color: lightcyan;
        }
        table caption {
            font-size: larger;
            margin-bottom: 8px;
        }
        body>p {
            display: flex;
        }
        p>a {
            text-decoration: none;
            color: #555;
            border: 1px solid;
            padding: 5px 10px;
            margin: 10px 2px;
        }
             /* 高亮 */
        .active {
            background-color: seagreen;
            color: white;
            border: 1px solid seagreen;
        }
    </style>
</head>
<body>
<table>
     <!-- 标题 -->
    <caption>员工信息表</caption>
    <!-- 表头  -->
    <thead>
        <tr>
            <td>ID</td>
            <td>姓名</td>
            <td>性别</td>
            <td>邮箱</td>
        </tr>
    </thead>
    <tbody>
 <?php
 foreach ($staffs as $staff):
    extract($staff);
?>
      <tr>
            <td><?=$id?></td>
            <td><?=$name?></td>
            <td><?=$sex?></td>
            <td><?=$email?></td>
        </tr>
     <?php endforeach ?> 
    </tbody>
</table>    
<!-- 分页条 
               <  ?php for():  ?>
    <        <  ?php endfor ? >   
    -->
    <p>
        <!-- 页面地址 -->
    <!-- <?php   echo $_SERVER['PHP_SELF'] .  '?p='  . 3;       ?> -->
    <?php  for($i=1;$i<= $pages;$i++):  ?>
        <!-- / /  页面跳转的 url    -->
         <?php   $url =  $_SERVER['PHP_SELF'] .  '?p='  . $i;      
        // 高亮设置   实现页面高亮  注意类型转换  将$_GET['p']  字符串型改为整数型
        //   $active =  ($i===Intval($_GET['p']))  ? 'active' : null;
              //   注意要个 第一页给个默认值  ，值为空的时候给默认值，有值不用
        // 目前还未做页码检查 ？？？？ 自行考虑
              $page = $_GET['p']??1;
              $active =  ($i===Intval($page))  ? 'active' : null;
          ?>
    <!-- 把地址塞到分页条            生成分页条样式                    生成分页数 -->
        <a href="<?=$url?>"  class="<?=$active?>"><?=$i?></a>
        <?php endfor ?>  
    </p>
</body>
</html>

<?php
// 加载zuoye3.php
require 'zuoye3.php';
echo'<hr>';
?>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>分页展示数据</title>
    <style>
        table {
            width: 400px;
            border-collapse: collapse;
            text-align: center;
        }
        table th,
        table td {
            border: 1px solid;
            padding: 5px;
        }
        table thead {
            background-color: lightcyan;
        }
        table caption {
            font-size: larger;
            margin-bottom: 8px;
        }
        body>p {
            display: flex;
        }
        p>a {
            text-decoration: none;
            color: #555;
            border: 1px solid;
            padding: 5px 10px;
            margin: 10px 2px;
        }
             /* 高亮 */
        .active {
            background-color: seagreen;
            color: white;
            border: 1px solid seagreen;
        }
    </style>
</head>
<body>
<table>
     <!-- 标题 -->
    <caption>员工信息表</caption>
    <!-- 表头  -->
    <thead>
        <tr>
            <td>ID</td>
            <td>姓名</td>
            <td>性别</td>
            <td>邮箱</td>
        </tr>
    </thead>
    <tbody>
 <?php
 foreach ($staffs as $staff):
    extract($staff);
?>
      <tr>
            <td><?=$id?></td>
            <td><?=$name?></td>
            <td><?=$sex?></td>
            <td><?=$email?></td>
        </tr>
     <?php endforeach ?> 
    </tbody>
</table>    
<!-- 分页条 
               <  ?php for():  ?>
    <        <  ?php endfor ? >   
    -->
    <p>
<?php 
    $uppage = $page-1;
    $upurl=  $_SERVER['PHP_SELF'] .  '?p='  .   $uppage;
  ?>
   <?php if($uppage>0):?>
<a href=<?=$upurl?>  >上一页</a>}
       <?php endif ?>
     <?php foreach($pgnull as $pg): ?>
        <?php
    if($pg==='...'){
        $url='#';
    }else {
        $url=  $_SERVER['PHP_SELF'] .  '?p='  . $pg;
    }
    $page = $_GET['p']??1;
    $active =  ($pg===Intval($page))  ? 'active' : null;
     ?>
     <a href="<?=$url?>"  class="<?=$active?>"><?=$pg?></a>
             <?php endforeach ?>
             <?php 
    $nextpage = $page + 1;
    $nexturl=  $_SERVER['PHP_SELF'] .  '?p='  . $nextpage;
    if($nextpage >$pages){
    // echo  '没有了';
    exit;
    }
?>
    <a href=<?=$nexturl?>>下一页</a>
    </p>
</body>
</html>

Correcting teacher：

PHPz

Correction status：qualified

Teacher's comments：

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将数据填充到前端的代码表格中

获取分页数据

获取总页数

分页展示数据

分页展示数据—-上一页、下一页