php分页代码学习示例分享_PHP

复制代码 代码如下:
    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 "

";
    echo "

php padding

";
    echo "";
    echo "";
    echo "";
    echo "";
    echo "";
    echo "";

    //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 "

";
        echo "";
        echo "";
    }

    echo "

ID	USER	PASS
{$row2['id']}	{$row2['name']}	{$row2['pass']}

";

    //上一页和下一页
    $prevpage = $page - 1;
    if ($page >= $totpage) {
        $nextpage = $totpage;
    } else {
        $nextpage = $page + 1;
    }

    //跳转
    echo "

上一页|下一页

";
    echo "";

核心点：

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

上一页和下一页的获得方式，以及临界点。