js实现一个省市区三级联动选择框代码分享

运行效果：
 
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部分代码：
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当然首先你数据库中要有这个table，不然你没有数据.....^_^
复制代码 代码如下:
<tr>
<td class="tr pr10 ">
所在地:
</td>
<td class="tl">
<input type="hidden" id="myProvince" value="${user.provinceId}"/>
<input type="hidden" id="myCity" value="${user.cityId}"/>
<input type="hidden" id="myRegion" value="${user.regionId}"/>
<select id="provinceSelect" name="user.provinceId">
<c:forEach items="${xzqhs}" var="xzqh">
<option value="${xzqh.provinceId}" ${user.regionId eq xzqh.provinceId?"selected='selected'":""}>${xzqh.province}</option>
</c:forEach>
</select>
<select id="citySelect" name="user.cityId">
</select>
<select id="regionSelect" name="user.regionId">
</select>
</td>
<td class="gray"></td>
</tr>

js代码：
复制代码 代码如下:
/**
* 加载市
*
*/
function loadCity() {
var provinceId = $("#provinceSelect option:selected").val();
if(provinceId == null || provinceId == ""){
//alert("找不到省");
}else{
$.post(rootPath+"/loadCity", {
"q" : provinceId
}, function(data, result) {
if(data == "noId"){
alert("请求错误");
}else if(data == "null"){
alert("系统找不到属于该省的市");
}else{
data = eval("{" + data + "}");
var citySelect = $("#citySelect");
var myCity = $("#myCity").val();
citySelect.html("");
for ( var i = 0; i < data.length; i++) {
if(myCity != null && myCity != "" && myCity > 0 && myCity == data[i].id){
citySelect.append("<option selected='selected' value='" + data[i].id + "'>"
+ data[i].name + "</option>");
}else{
citySelect.append("<option value='" + data[i].id + "'>"
+ data[i].name + "</option>");
}
}
loadRegion();
}
});
}
};
/**
* 加载区
*
*/
function loadRegion() {
var cityId = $("#citySelect option:selected").val();
if(cityId == null || cityId == "" || cityId < 1){
alert("找不到市");
}else{
$.post(rootPath+"/loadRegion", {
"q" : cityId
}, function(data, result) {
if(data == "noId"){
alert("请求错误");
}else if(data == "null"){
alert("系统找不到属于该市的区");
}else{
data = eval("{" + data + "}");
var regionSelect = $("#regionSelect");
var myRegion = $("#myRegion").val();
regionSelect.html("");
for ( var i = 0; i < data.length; i++) {
if(myRegion != null && myRegion != "" && myRegion > 0 && myRegion == data[i].id){
regionSelect.append("<option selected='selected' value='" + data[i].id + "'>"
+ data[i].name + "</option>");
}else{
regionSelect.append("<option value='" + data[i].id + "'>"
+ data[i].name + "</option>");
}
}
}
});
}
};
/**
* 省改变事件
*
*/
$("#provinceSelect").change(loadCity);
/**
* 市改变事件
*
*/
$("#citySelect").change(loadRegion);

$(function() {
loadCity();
});

后台方法：
复制代码 代码如下:
/**
* 加载城市数据
*
*/
public void loadCity() {
if (q == null || q.trim().equals("")) {
write("noId");
} else {
List<Xzqh> citys = xzqhService.queryCitys(q.trim());
if (citys == null || citys.size() < 1) {
write("null");
} else {
StringBuilder builder = new StringBuilder("[");
for (Xzqh city : citys) {
builder.append("{'id':'");
builder.append(city.getCityId());
builder.append("','name':'");
builder.append(city.getCity());
builder.append("'},");
}
if (builder.length() > 1)
builder.replace(builder.length() - 1, builder.length(), "]");
write(builder.toString());
}
}
}
/**
* 加载区数据
*
*/
public void loadRegion() {
if (q == null || q.trim().equals("")) {
write("noId");
} else {
List<Xzqh> citys = xzqhService.queryDistricts(q.trim());
if (citys == null || citys.size() < 1) {
write("null");
} else {
StringBuilder builder = new StringBuilder("[");
for (Xzqh district : citys) {
builder.append("{'id':'");
builder.append(district.getRegionId());
builder.append("','name':'");
builder.append(district.getRegion());
builder.append("'},");
}
if (builder.length() > 1)
builder.replace(builder.length() - 1, builder.length(), "]");
write(builder.toString());
}
}
}