没有数据时如何隐藏选择选项

Question

我正在构建一个下拉列表，其中包含来自数据库的数据的选项，并希望隐藏具有零数据的选项。

我尝试了一个 if 语句使用 continue 但未能从数据库中捕获实时数据值。

      <select name='Database' title="Choose from database">

        <option value="">All</option>

        <?php foreach($database as $row):

          if ($row['topic'] == 0) {

            continue;

          }

          else {

          ?>

            <option value="<?= $row['topic']; ?>"

            <?php if ($row['topic'] == $_SESSION['prosess']){echo " 

            selected";}?>>

            <?= $row['topic']; ?>

          <?php }?>

          </option>

        <?php endforeach; ?>

      </select>

是否有任何巧妙的 javascript-、php- 等代码可以停用/隐藏数据库中的空选项。

Answer 1

我想你应该试试这个。<select name='Database' title="Choose from database">&nbsp; &nbsp; <option value="">All</option>&nbsp; &nbsp; <?php&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; if(count($database) > 0)&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; foreach($database as $row)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; ?>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <option value="<?= $row['topic']; ?>"&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <?php if ($row['topic'] == $_SESSION['prosess']){echo "&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; selected";}?>>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <?= $row['topic']; ?>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <?php }?>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </option>&nbsp; &nbsp; <?php&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp;&nbsp; &nbsp; ?></select>希望对你有帮助。

Answer 2

在你的css中添加这个：选择选项：空{显示：无}