implode如何能改成可以修改的页面

 <td class="title" width="180">上级关系：</td>
            <td><?=implode('> ',$this->getCol("select username from {$this->prename}members where uid in ({$userData['parents']})"))?></td>
        </tr>

图片说明
图片说明

我改成这样，然后就悲剧了

    <td class="title" width="180">上级关系：</td>
            <td><input type="text" name="parents" value="<?=implode('> ',$this->getCol("select username from {$this->prename}members where uid in ({$userData['parents']})"))?>" />&nbsp;</td>

图片说明
图片说明
样子到是想要的样子