php 分页在网站开发中扮演着重要角色,能够帮助网页内容分页显示,提高用户体验。php小编西瓜将为大家介绍如何使用php实现分页功能,让网站更加易于浏览和管理。通过本文的学习,读者可以轻松掌握php分页的原理和实现方法,为网站开发增添新的技能和灵感。
我们还将演示另一种在 PHP 分页中添加 Previous
和 Next
导航功能的方法。此方法仅添加了将相应页面导航到第一种方法的附加功能。
在 PHP 中在 SQL
中使用 LIMIT
子句和 SELECT
语句对行进行分页
我们可以使用 LIMIT
子句和 SELECT
语句来指定要在页面上显示的前 n 个结果。我们可以在 anchor
标签中提供页码作为 GET
方法来浏览页面。在此方法中,我们定义每页要显示的行数,并从数据库中检索所有行以计算所需的总页数。我们可以使用 $_GET
数组和 isset()
函数来获取用户请求的页码。
例如,创建一个变量 $results_per_page
并在其中存储 2
。使用 Mysqli_num_rows()
函数查找数据库中的行数并存储在 $number_of_results
变量中。使用 ceil()
函数来确定显示行所需的总页数。将 $number_of_results
变量除以 ceil()
函数内的 $results_per_page
变量。使用 $_GET
超全局变量和 isset()
函数来检查 page
变量是否已设置。如果尚未设置,请将 $page
变量设置为 1
。如果已设置变量,则将值分配给 $page
变量。用 1
减去 $page
变量并将其乘以 $this_page_first_result
变量。将操作存储在变量 $this_page_first_result
中。编写一个带有 LIMIT
子句的 SQL
语句为 SELECT * FROM alpha LIMIT ' . $this_page_first_result . ',' . $results_per_page.
运行查询并显示结果。最后,创建一个 for
循环以在 $page
变量和 $number_of_page
之间循环。在循环内,echo
anchor
标签并将 href
属性的值设置为 index.php?page'.$page
。在 anchor
标签之间写入 $page
变量。
在下面的示例中,数据库中的 alpha
表包含六行。执行分页后,每页显示两行。ceil()
函数确定显示行所需的总页数。最初,$page
变量未设置,因此页面从第 1 页开始。$this_page_first_result
变量确定用户当前所在的页码。变量 $this_page_first_result
表示页面的第一行。变量 $results_per_page
表示每页的结果数。输出部分显示 index.php
页面。当点击页面 2
时,它会从数据库中输出接下来的两行。
示例代码:
<code class="language-php hljs" data-lang="php"><span style="display:flex;"><span><span style="color:#408080;font-style:italic">#php 7.x
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#666"></span>php
</span></span><span style="display:flex;"><span><span style="color:#19177c">$number_of_pages</span> <span style="color:#666">=</span> ceil(<span style="color:#19177c">$number_of_results</span><span style="color:#666">/</span><span style="color:#19177c">$results_per_page</span>);
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">if</span> (<span style="color:#666">!</span>isset(<span style="color:#19177c">$_GET</span>[<span style="color:#ba2121">'page'</span>])) {
</span></span><span style="display:flex;"><span><span style="color:#19177c">$page</span> <span style="color:#666">=</span> <span style="color:#666">1</span>;
</span></span><span style="display:flex;"><span>} <span style="color:#008000;font-weight:bold">else</span> {
</span></span><span style="display:flex;"><span><span style="color:#19177c">$page</span> <span style="color:#666">=</span> <span style="color:#19177c">$_GET</span>[<span style="color:#ba2121">'page'</span>];
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#19177c">$this_page_first_result</span> <span style="color:#666">=</span> (<span style="color:#19177c">$page</span><span style="color:#666">-</span><span style="color:#666">1</span>)<span style="color:#666">*</span><span style="color:#19177c">$results_per_page</span>;
</span></span><span style="display:flex;"><span><span style="color:#19177c">$sql</span><span style="color:#666">=</span><span style="color:#ba2121">'SELECT * FROM alpha LIMIT '</span> <span style="color:#666">.</span> <span style="color:#19177c">$this_page_first_result</span> <span style="color:#666">.</span> <span style="color:#ba2121">','</span> <span style="color:#666">.</span> <span style="color:#19177c">$results_per_page</span>;
</span></span><span style="display:flex;"><span><span style="color:#19177c">$result</span> <span style="color:#666">=</span> <strong class="keylink">mysql</strong>i_query(<span style="color:#19177c">$con</span>, <span style="color:#19177c">$sql</span>);
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">while</span>(<span style="color:#19177c">$row</span> <span style="color:#666">=</span> mysqli_fetch_array(<span style="color:#19177c">$result</span>)) {
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#19177c">$row</span>[<span style="color:#ba2121">'id'</span>] <span style="color:#666">.</span> <span style="color:#ba2121">' '</span> <span style="color:#666">.</span> <span style="color:#19177c">$row</span>[<span style="color:#ba2121">'value'</span>]<span style="color:#666">.</span> <span style="color:#ba2121">'<br>'</span>;
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">for</span> (<span style="color:#19177c">$page</span><span style="color:#666">=</span><span style="color:#666">1</span>;<span style="color:#19177c">$page</span><span style="color:#666"><span style="color:#19177c">$number_of_pages</span>;<span style="color:#19177c">$page</span><span style="color:#666">++</span>) {
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">'<a href="index.php?page='</span>%20<span%20style=" color:>.</a></span> <span style="color:#19177c">$page</span> <span style="color:#666">.</span> <span style="color:#ba2121">'">'</span> <span style="color:#666">.</span> <span style="color:#19177c">$page</span> <span style="color:#666">.</span> <span style="color:#ba2121">' '</span>;
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#bc7a00">?></span><span >
</span></span></span></span>
输出:
<code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>1 A
</span></span><span style="display:flex;"><span>2 B
</span></span><span style="display:flex;"><span>1 2 3
</span></span>
在 PHP 的分页中添加 Previous
和 Next
导航功能
我们可以在第一种方法的代码示例中添加一些额外的代码片段,以在分页中提供 Previous
和 Next
导航功能。我们可以将 $page
变量递增和递减 1 以指向上一页和下一页。我们可以使用 anchor
标签中的递增和递减变量来实现 Next
和 Previous
功能。
例如,创建两个变量,$prev
和 $next
。用 1 减去 $page
变量并将操作分配给 $prev
变量。类似地,将 1 添加到 $page
变量并将其分配给 $next
变量。在页码的 for
循环之前回显一个 anchor
标签,上面写着 Previous
。将 anchor
标签的 href
属性赋值为 index.php?page=' . $prev .
。以同样的方式,使用 $next
变量作为 href
属性中 page
的值,为 Next
创建另一个 anchor
标记。
在下面的输出部分,它显示了第二页。单击 Previous
进入第一页,单击 Next
进入第三页。
示例代码:
<code class="language-php hljs" data-lang="php"><span style="display:flex;"><span><span style="color:#408080;font-style:italic"># php 7.x
</span></span></span><span style="display:flex;"><span><span style="color:#408080;font-style:italic"></span><span style="color:#666"></span>php
</span></span><span style="display:flex;"><span><span style="color:#19177c">$prev</span> <span style="color:#666">=</span> <span style="color:#19177c">$page</span> <span style="color:#666">-</span><span style="color:#666">1</span>;
</span></span><span style="display:flex;"><span><span style="color:#19177c">$next</span> <span style="color:#666">=</span> <span style="color:#19177c">$page</span> <span style="color:#666">+</span><span style="color:#666">1</span>;
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">' <a href="index.php?page='</span>%20<span%20style=" color:>.</a></span> <span style="color:#19177c">$prev</span> <span style="color:#666">.</span> <span style="color:#ba2121">'"> Previous '</span>;
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">for</span> (<span style="color:#19177c">$page</span><span style="color:#666">=</span><span style="color:#666">1</span>;<span style="color:#19177c">$page</span><span style="color:#666"><span style="color:#19177c">$number_of_pages</span>;<span style="color:#19177c">$page</span><span style="color:#666">++</span>) {
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">'<a href="index.php?page='</span>%20<span%20style=" color:>.</a></span> <span style="color:#19177c">$page</span> <span style="color:#666">.</span> <span style="color:#ba2121">'">'</span> <span style="color:#666">.</span> <span style="color:#19177c">$page</span> <span style="color:#666">.</span> <span style="color:#ba2121">' '</span>;
</span></span><span style="display:flex;"><span>}
</span></span><span style="display:flex;"><span><span style="color:#008000;font-weight:bold">echo</span> <span style="color:#ba2121">' <a href="index.php?page='</span>%20<span%20style=" color:>.</a></span> <span style="color:#19177c">$next</span> <span style="color:#666">.</span> <span style="color:#ba2121">'"> Next '</span>;
</span></span><span style="display:flex;"><span><span style="color:#bc7a00">?></span><span >
</span></span></span></span>
输出:
<code class="language-text hljs" data-lang="text"><span style="display:flex;"><span>3 C
</span></span><span style="display:flex;"><span>4 D
</span></span><span style="display:flex;"><span>Previous 1 2 3 Next
</span></span>