php分页代码学习示例分享

  

复制代码 代码如下:

  <?php

  header("content-type:text/html;charset=utf-8");

  //数据库连接

  $conn = mysql_connect("localhost", "root", "111") or die("not connnected : ".mysql_error());

  mysql_select_db("test", $conn);

  mysql_query("set names utf8");

  //查询共有多少行数据

  $sql1 = "select count(*) from user";

  $ret1 = mysql_query($sql1);

  $row1 = mysql_fetch_row($ret1);

  $tot = $row1[0];

  //每页多少行数据

  $length = 5;

  //总页数

  $totpage = ceil($tot / $length);

  //当前页数

  $page = @$_GET['p'] ? $_GET['p'] : 1;

  //limit 下限

  $offset = ($page - 1) * $length;

  echo "<center>";

  echo "<h2>php padding</h2>";

  echo "<table width='700px' border='1px' >";

  echo "<tr>";

  echo "<th>ID</th>";

  echo "<th>USER</th>";

  echo "<th>PASS</th>";

  echo "</tr>";

  //将查询出来的数据用表格显示

  $sql2 = "select * from user order by id limit {$offset}, {$length}";

  $ret2 = mysql_query($sql2);

  while ($row2 = mysql_fetch_assoc($ret2)) {

  echo "<tr>";

  echo "<td>{$row2['id']}</td><td>{$row2['name']}</td><td>{$row2['pass']}</td>";

  echo "</tr>";

  }

  echo "</table>";

  //上一页和下一页

  $prevpage = $page - 1;

  if ($page >= $totpage) {

  $nextpage = $totpage;

  } else {

  $nextpage = $page + 1;

  }

  //跳转

  echo "<h3><a href='index.php?p={$prevpage}'>上一页</a>|<a href='index.php?p={$nextpage}'>下一页</a></h3>";

  echo "</center>";

  核心点:

  <1>“$sql2 = "select * from user order by id limit {$offset}, {$length}";”,$offset、$length和页数之间的关系。

  <2>上一页和下一页的获得方式,以及临界点。