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。