php mysql多选，下拉菜单，不存回数据库

<form action="process.php" method="post">
  <label for="multi-select">多选：</label>
  <select name="multi-select[]" multiple>
    <option value="option1">选项1</option>
    <option value="option2">选项2</option>
    <option value="option3">选项3</option>
  </select>
  
  <br>
  
  <label for="dropdown">下拉菜单：</label>
  <select name="dropdown">
    <option value="option1">选项1</option>
    <option value="option2">选项2</option>
    <option value="option3">选项3</option>
  </select>
  
  <br>
  
  <input type="submit" value="提交">
</form>

$multiSelect = $_POST['multi-select'];
$dropdown = $_POST['dropdown'];

// 处理多选
foreach ($multiSelect as $option) {
  echo $option . "<br>";
}

// 处理下拉菜单
echo $dropdown;