我正在尝试使用jQuery / AJAX和PHP / MySQL创建一组动态下拉框。页面加载时,第一个下拉框将根据数据库中的值进行填充。第二个下拉框应该显示基于第一个下拉框的选择的一组值。我知道这里以前有类似的问题,但我没有找到与我的情况匹配的解决方案。
生成用于第二个下拉列表的JSON编码值列表的查询正在运行,但我在将其填充到实际的下拉表单元素中遇到问题。您对我做错了什么有什么想法吗?
Javascript:
生成用于第二个下拉列表的JSON编码值列表的查询正在运行,但我在将其填充到实际的下拉表单元素中遇到问题。您对我做错了什么有什么想法吗?
Javascript:
<script>
$().ready(function() {
$("#item_1").change(function () {
var group_id = $(this).val();
$.ajax({
type: "POST",
url: "../../db/groups.php?item_1_id=" + group_id,
dataType: "json",
success: function(data){
//Clear options corresponding to earlier option of first dropdown
$('select#item_2').empty();
$('select#item_2').append('<option value="0">Select Option</option>');
//Populate options of the second dropdown
$.each( data.subjects, function(){
$('select#item_2').append('<option value="'+$(this).attr('group_id')+'">'+$(this).attr('name')+'</option>');
});
$('select#item_2').focus();
},
beforeSend: function(){
$('select#item_2').empty();
$('select#item_2').append('<option value="0">Loading...</option>');
},
error: function(){
$('select#item_2').attr('disabled', true);
$('select#item_2').empty();
$('select#item_2').append('<option value="0">No Options</option>');
}
})
});
});
</script>
HTML:
<label id="item_1_label" for="item_1" class="label">#1:</label>
<select id="item_1" name="item_1" />
<option value="">Select</option>
<?php
$sth = $dbh->query ("SELECT id, name, level
FROM groups
WHERE level = '1'
GROUP by name
ORDER BY name");
while ($row = $sth->fetch ()) {
echo '<option value="'.$row['id'].'">'.$row['name'].'</option>'."\n";
}
?>
</select>
<label id="item_2_label" for="item_2" class="label">#2:</label>
<select id="item_2" name="item_2" />
</select>
PHP:
<?php
require_once('../includes/connect.php');
$item_1_id = $_GET['item_1_id'];
$dbh = get_org_dbh($org_id);
$return_arr = array();
$sth = $dbh->query ("SELECT id, name, level
FROM groups
WHERE level = '2'
AND parent = $item_1_id
GROUP by name
ORDER BY name");
while ($row = $sth->fetch ()) {
$row_array = array("name" => $row['name'],
"id" => $row['id']);
array_push($return_arr,$row_array);
}
echo json_encode($return_arr);
?>
示例JSON输出:
[{"name":"A","id":"0"},{"name":"B","id":"1"},{"name":"C","id":"2"}]