Question

我现在遇到了一些问题，我的代码有些奇怪的行为，无法找到原因。

我有一张分配给qeue的分机表（电话）。我通过SQL查询获取数据，然后在屏幕上显示它。其中一个显示的数据是优先级，我希望通过选择下拉列表中的新选项来更改jquery + ajax。

所以，我管理了这段代码：

echo '<table cellpadding="5" cellspacing="0" width="30%" id="deletion" bgcolor="#f6f6f6" style="border:1px solid #cccccc;">
        <tr>
            <th><strong>Extension</strong></th>
            <th><strong>Priority</strong></th>
            <th>&nbsp;</th>
        </tr>';
        while ($datos_extension = mysql_fetch_array($result)){
                echo '<tr id="'.$extension_data['id'].'"><td>'.$extension_data['extension'].'</td><td>'.show_priority($datos_extension['priority']).'</td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr>';
            }
        echo "</table>";

现在，功能：

function show_priority ($priority) {
    $max_priority = 3;
    $cont = 1;

    echo '<select name="priority" class="priority">';

    while ($cont <= $max_priority) {
        echo '<option';
        if ($cont == $priority)
            echo " selected";
        echo ' value="'.$cont.'">'.$cont.'</option>';
        $cont ++;
    }
    echo "</select>";
}

但是它显示了表格中的下拉菜单......这是HTML输出：

<tr>
            <th><strong>Extension</strong></th>
            <th><strong>Priority</strong></th>

            <th>&nbsp;</th>
        </tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="2"><td>1002</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="3"><td>1003</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="4"><td>1004</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="5"><td>1005</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="6"><td>1006</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="7"><td>1007</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="8"><td>1008</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option selected value="1">1</option><option value="2">2</option><option value="3">3</option></select><tr id="9"><td>1009</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr><select name="priority" class="priority"><option value="1">1</option><option selected value="2">2</option><option value="3">3</option></select><tr id="10"><td>9003</td><td></td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr></table>

有人知道问题出在哪里吗？

Answer 1

我认为这是因为嵌套的echo语句。所以在PHP缓存第一个echo之前它会显示第二个，因为它在里面。我认为该解决方案是在show_priority函数内部构建字符串并返回它，如：


function show_priority ($priority) {
    $max_priority = 3;
    $cont = 1;

    $return = '<select name="priority" class="priority">';

    while ($cont <= $max_priority) {
        $return .= '<option';
        if ($cont == $priority)
            $return .= " selected=selected"; //this should be done like this in proper HTML
        $return .= ' value="'.$cont.'">'.$cont.'</option>';
        $cont ++;
    }
    $return .= "</select>";

    return $return;
}

我没有测试过，但我相信它会起作用。

Answer 2

这是因为echo的所有代码在输出最终刺痛之前都会被执行。该函数在父echo填充表行之前回显列表。您需要更改此功能才能将其插入其他字符串中：

function show_priority ($priority) {
    $max_priority = 3;
    $cont = 1;
    $output = '';

    $output .= '<select name="priority" class="priority">';

    while ($cont <= $max_priority) {
        $output .= '<option';
        if ($cont == $priority)
            $output .= " selected";
        $output .= ' value="'.$cont.'">'.$cont.'</option>';
        $cont ++;
    }
    $output .= "</select>";
    return $output;
}

但毕竟最好将列表作为数组或对象返回，然后在生成所有内容后单独填充它;将数据库逻辑与设计分开。

如果由于某种原因您无法改变功能，您可以使用输出缓冲：

    while ($datos_extension = mysql_fetch_array($result)){
            ob_start();
            show_priority($datos_extension['priority']);
            echo '<tr id="'.$extension_data['id'].'"><td>'.$extension_data['extension'].'</td><td>'.ob_get_clean().'</td><td><a href="#" class="delete negative button"><span class="cross icon"></span>Delete</a></td></tr>';
   }

下拉列表奇怪地显示在表格外面

2 个答案: