下面我有一段代码，它假设显示 2 个下拉菜单，一个用于建筑，另一个用于房间。发生的情况是，当用户从建筑物下拉菜单中选择建筑物时，使用 ajax/jquery 它将导航到room.php页面并列出属于所选建筑物的房间，并在房间下拉菜单中显示房间列表。这工作正常：
<script type="text/javascript">
function getRooms() {
var building = jQuery("#buildingsDrop").val();
jQuery('#roomsDrop').empty();
jQuery('#roomsDrop').html('<option value="">Please Select</option>');
jQuery.ajax({
type: "post",
url: "room.php",
data: { building:building },
success: function(response){
jQuery('#roomsDrop').append(response);
}
});
}
</script>
...
<?php
$sql = "SELECT DISTINCT Building FROM Room";
$sqlstmt=$mysqli->prepare($sql);
$sqlstmt->execute();
$sqlstmt->bind_result($dbBuilding);
$buildings = array(); // easier if you don't use generic names for data
$buildingHTML = "";
$buildingHTML .= '<select name="buildings" id="buildingsDrop" onchange="getRooms();">'.PHP_EOL;
$buildingHTML .= '<option value="">Please Select</option>'.PHP_EOL;
while($sqlstmt->fetch())
{
$building = $dbBuilding;
$buildingHTML .= "<option value='".$building."'>" . $building . "</option>".PHP_EOL;
}
$buildingHTML .= '</select>';
$roomHTML = "";
$roomHTML .= '<select name="rooms" id="roomsDrop">'.PHP_EOL;
$roomHTML .= '<option value="">Please Select</option>'.PHP_EOL;
$roomHTML .= '</select>';
?>
房间.php：
$building = isset($_POST['building']) ? $_POST['building'] : '';
$sql = "SELECT Room FROM Room WHERE Building = ?";
$sqlstmt=$mysqli->prepare($sql);
$sqlstmt->bind_param("s",$building);
$sqlstmt->execute();
$sqlstmt->bind_result($dbRoom);
$roomHTML = "";
while($sqlstmt->fetch()) {
$roomHTML .= "<option value='".$dbRoom."'>" . $dbRoom . "</option>".PHP_EOL;
}
echo $roomHTML;
我遇到的问题是当用户选择评估时，假设在相关下拉菜单中显示评估的建筑和房间选项。但它并没有选择那些选项，它们保留在“请选择”选项上。为什么会这样，我怎样才能获得显示的选项？
下面是查看源代码：
//Assessment drop down menu:
<p><strong>Assessments:</strong> <select name="session" id="sessionsDrop">
<option value="">Please Select</option>
<option value='71' style='color: green'>AKXMB - 30-11-2012 - 10:00</option>
</select> </p>
</form>
//Building drop down menu:
<select name="buildings" id="buildingsDrop" onchange="getRooms();">
<option value="">Please Select</option>
<option value='Canalside East'>Canalside East</option>
<option value='Canalside West'>Canalside West</option>
</select>
//Room drop down menu (list of rooms displayed in room.php):
<select name="rooms" id="roomsDrop">
<option value="">Please Select</option>
</select>
//Retrieve assessment information
//(Below is where problem lies where it is not selecting building and room options in drop down menu)
<script type="text/javascript">
$(document).ready( function(){
var sessioninfo = [{"SessionId":71,"Building":"Canalside East","Room":"CE01\/04"},{"SessionId":84,"Building":"Canalside East","Room":"CE01\/04"}];
$('#sessionsDrop').change( function(){
var sessionId = $(this).val();
if (sessionId !== '') {
for (var i = 0, l = sessioninfo.length; i < l; i++)
{
if (sessioninfo[i].SessionId == sessionId) {
var currentbuilding = $('#currentBuilding').val(sessioninfo[i].Building);
var editbuilding = $('#BuildingsDrop').val(sessioninfo[i].Building);
var currentroom = $('#currentRoom').val(sessioninfo[i].Room);
var editroom = $('#RoomsDrop').val(sessioninfo[i].Room);
var currentid = $('#currentId').val(sessioninfo[i].SessionId);
var editid = $('#newId').val(sessioninfo[i].SessionId);
break;
}
}
}
});
});
</script>
更新：
在应用程序中，从下拉菜单中选择“模块”并提交。
它下面应该显示一些功能。在评估下拉菜单中选择任何评估。
您可以在“当前评估详细信息”下方看到它在只读文本输入中显示建筑物和房间，以指示评估的当前建筑物和房间是什么。
我希望在“新评估室”部分的下拉菜单中选择相同的建筑物和房间。您可以看到在“建筑物”下拉菜单中选择了建筑物，但在“房间”下拉菜单中未选择“房间”。