我有三个相互依赖的下拉菜单。根据下拉列表A的选择,将在下拉列表B中显示结果列表,并根据下拉列表B的选择将在下拉列表C中显示结果列表。
我可以毫无问题地填充前两个下拉列表。但是,最后一个下拉列表确实显示了错误的选项。
$(function() {
var platforms;
var tasktypes;
var compos;
var jsonData;
$('#addnew').click(function(){
$('#dataset').clone().appendTo($('#newfield'));
});
$.getJSON('tasks.json', function(result) {
jsonData = result;
$.each(result, function(i, platform) {
platforms += "<option value='" +
platform.name +
"'>" +
platform.name +
"</option>";
});
$('#platform').html(platforms);
});
$("#platform").change(function (){
var idx = $("#platform").prop('selectedIndex');
var platforms = jsonData[idx].task;
tasktypes = "";
for (i = 0; i < platforms.length; i++) {
tasktypes += "<option value='" +
platforms[i].taskname +
"'>" +
platforms[i].taskname +
"</option>";
};
$('#taskname').html(tasktypes);
});
$("#taskname").change(function (){
var idc = $("#taskname").prop('selectedIndex');
var tasktypes = jsonData[idc].task[0].component;
compos = "";
for (i = 0; i < tasktypes.length; i++) {
compos += "<option value='" +
tasktypes[i].componentname +
"'>" +
tasktypes[i].componentname +
"</option>";
};
$('#components').html(compos);
});
});
<!DOCTYPE html>
<html>
<head>
<title>test</title>
</head>
<body>
<button id="addnew">Add new</button>
<div id="dataset">
Platform:
<select id="platform">
</select>
Task Type:
<select id="taskname">
</select>
Component:
<select id="components">
</select>
Units:
<input type="number" min="0" />
</div>
<div id="newfield"></div>
<button id="calculate">Calculate</button>
<button id="clear">Clear</button>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
</body>
</html>
的Json
[
{
"name": "Sitecore",
"value": "sitecore",
"task": [
{
"taskname": "promobox",
"component": [
{
"componentname": "A",
"time": "20"
},
{
"componentname": "B",
"time": "10"
}
]
},
{
"taskname": "video",
"component": [
{
"componentname": "C",
"time": "20"
},
{
"componentname": "D",
"time": "10"
}
]
}
]
},
{
"name": "Siab",
"value": "siab",
"task": [
{
"taskname": "promobox",
"component": [
{
"componentname": "E",
"time": "20"
},
{
"componentname": "F",
"time": "10"
}
]
},
{
"taskname": "newswire",
"component": [
{
"componentname": "G",
"time": "20"
},
{
"componentname": "H",
"time": "10"
}
]
},
{
"taskname": "video",
"component": [
{
"componentname": "I",
"time": "20"
},
{
"componentname": "J",
"time": "10"
}
]
}
]
}
]
前两个下拉列表工作正常。从第一个下拉列表中选择一个平台后,第二个下拉列表将填充相关的任务名称。但是,一旦我从第二个下拉列表中选择了一个任务名称,第三个下拉列表就会显示无关的数据。我无法弄清楚我在这里做错了什么。
答案 0 :(得分:0)
我认为在ajax请求期间,您遇到的主要问题是jsonData = result
。默认情况下,所有ajax请求都是异步的,因此,在请求完成后,从它生成的每个数据通常都不存在。因此,最好的办法是在请求期间将result
传递给HTML DOM对象。
$.getJSON('tasks.json', function(result) {
$('#platform').data('jsonData',result);//Assign Json data to data object of platform id
$.each(result, function(i, platform) {
platforms += "<option value='" +
platform.name +
"'>" +
platform.name +
"</option>";
});
$('#platform').html(platforms);
});