我有一个带有复选框的下拉菜单。我可以通过单击复选框来选择多个项目。但无法通过单击下拉框中的项目名称进行选择。现在，当我点击name而不是checkbox时，光标会移到网页的顶部，在下拉菜单中没有选择任何内容。有没有办法，我可以点击多个下拉菜单项，他们被选中？我的代码如下：

<div id="parents"  style="display:block">   
     <div class="col-sm-5">
      <div class="dropdown test">
         &nbsp;<button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown" name="single[]" id="single">Select Event Singles
           <span class="caret"></span></button>
                <ul class="dropdown-menu" >
                <?php

     $mysqli = new mysqli("localhost", "user", "passwd", "db_name") or die("could not connect to database") . "<br>";
                                    $result = $mysqli->query("SELECT EventID,Event_Name FROM events where EventID IN (2,3,4,5,6,8,9,10,12,16,17,18,20)");
                                    if ($result->num_rows > 0) {
                                        // output data of each row
                                        while ($row = $result->fetch_assoc()) {

                                            echo "<li><a href='#' class='test'><input type='checkbox' name='frames[]' value='".$row['EventID']."' >" . $row["Event_Name"] . "</input></a></li>";
                                        }

                                    }
                                    $mysqli->close();
                                    ?>
                                </ul>
                            </div>
                        </div>