Question

if (isset($_GET['order']) && $_GET['order'] == 'category')
{

    $sql .= " ORDER BY category ".$_GET["direction"];
}

<a href='?order=category&direction=ASC'>

当用户第二次单击链接时，我要按DESC顺序对表进行排序。当用户单击相同的链接时，我需要按a-z顺序将其撤消。

Answer 1

您可以切换会话/ cookie中的单击状态。

if (isset($_GET['order']) && $_GET['order'] == 'category') {
  $sql .= " ORDER BY category ".$_GET["direction"];
  $dir = $_GET['direction'] == 'ASC' ? 'DESC' : 'ASC';
 }
 if($_SESSION['click'] == 0){
    echo "<a href='?order=category&direction=ASC'>";
 } else{ 
    echo "<a href='?order=category&direction=DESC'>";
 }

Answer 2

只需检查$_GET['direction']中包含的内容，并在每次运行提交时将其反转。

另外，要照顾页面重新加载，请在会话中保存前一个方向的值。

$dir = 'DESC'; // set default for first execution
@session_start(); // start the session if it isn't already started.
if(!empty($_GET['direction'])){
  $dir = $_GET['direction'] == 'ASC' ? 'ASC' : 'DESC'; // avoids SQL injection.
  $_SESSION['direction'] = $dir;
}elseif(!empty($_SESSION['direction'])){
  $dir = $_SESSION['direction'];
 }
if (isset($_GET['order']) && $_GET['order'] == 'category') {
    $sql .= " ORDER BY category ".$dir;
}

$reverseDir= $dir =='DESC' ? 'ASC' : 'DESC'; //reverses the direction to be used in the link
<a href='?order=category&direction='<?php echo $reverseDir;?>>

ASC DESC在同一链接中

2 个答案: