Question

我试图为我的投递箱添加占位符，该投放箱可以获取mySQL的结果，而且我不知道是否有办法。

<div class="select_drp">
    <?php
        $query = mysql_query("SELECT * FROM training_list"); 
        echo '<select class="select_drp" name="insert_training" required>'; 
        while ($row = mysql_fetch_array($query)) {
           echo '<option value="'.$row['id'].'">'.$row['training_type'].'</option>';
        }
        echo '</select>';
        echo "<br/><br/>";
    ?>
</div>

Answer 1

检查一下，我添加<option value="">Placeholder</option>，我想你可以使用它作为占位符。

<div class="select_drp">
    <?php
    $query = mysql_query("SELECT * FROM training_list");
    echo '<select class="select_drp" name="insert_training" required>';
    echo '<option value="">Placeholder</option>';
    while ($row = mysql_fetch_array($query)) {
        echo '<option value="' . $row['id'] . '">' . $row['training_type'] . '</option>';
    }
    echo '</select>';
    echo "<br/><br/>";
    ?>
</div>

Answer 2

试试这个：

<div class="select_drp">
    <?php
        $query = mysql_query("SELECT * FROM training_list"); 
        echo '<select class="select_drp" name="insert_training" required>'; 
        echo '<option value="" disabled selected style="display: none;">Please Choose</option>'; //This line your placeholder
        while ($row = mysql_fetch_array($query)) {
           echo '<option value="'.$row['id'].'">'.$row['training_type'].'</option>';
        }
        echo '</select>';
        echo "<br/><br/>";
    ?>
</div>

Answer 3

如果你在MySQL的结果中谈论选项，你可以像那样禁用它

echo '<option value="'.$row['id'].'" disabled>'.$row['training_type'].'</option>';

如果你在选择下拉列表中的占位符以及来自MySQL的结果在循环之前简单地说出另一个

<select>
    <option value="">placeholder</option>
    <?php
       ...
       while ( ... ) {
            echo '<option value="'.$row['id'].'">'.$row['training_type'].'</option>';
       }
     ?>
 </select>

如何制作占位符以便选择＆＃39;从mySQL获取数据的方框？

3 个答案: