如何在使用PHP/HTML更新时保存下拉列表选项 - How to save drop-down list choice upon update using PHP/HTML?

How to save drop-down list choice upon update using PHP/HTML?

我想创建一个下拉列表，允许用户选择从数据库中提取的值。根据所选值更新页面时，该选项将恢复为"原始"默认选项。如何允许所选值在页面更新时保存并保留？

// Drop Down Menu to choose Session
if (isset($_POST['action']))
{
    $action = $_POST['action'];
    $session = $_POST['session'];
}
else
{
    $action = "";
    if (!isset($_POST['session']))
    {
        $session = "";
    }
    else
    {
        $session = $_POST['session'];
    }
}
?>
<form name='update' action='emailinquiry_webinarnew.php' method='POST'>
Session: 
<select name='session'>
    <?php
    $query = "SELECT distinct session FROM web_attendees";
    $result = mysql_query($query) or die(mysql_error());
    while ($row = mysql_fetch_assoc($result))
    {
        echo "<option>".$row['session']."</option>";
    }
    ?>
</select>
<input type='submit' name="ViewButton" value='View'/>
</form>

while ($row = mysql_fetch_assoc($result))  {
    if($row['session']==$session){
        echo "<option selected='selected' >".$row['session']."</option>";
    } else {
        echo "<option >".$row['session']."</option>";
    }
}

希望它对你有用。。。

只需在打印选项的while循环中添加这样的条件即可添加默认选择选项的selected="selected"：

while ($row = mysql_fetch_assoc($result))
{
    $selected = '';
    if (isset($_POST['session']) && $row['session'] == $_POST['session'])
        $selected = ' selected="selected"';
    echo "<option{$selected}>".$row['session']."</option>";
}