package com.hanqi.entity;

//地区

public class Region {

    //地区id

    private String regionID;

    //地区名称

    private String regionName;

    //上级地区id

    private String parentRegionID;

    public String getRegionID() {

        return regionID;

    }

    public void setRegionID(String regionID) {

        this.regionID = regionID;

    }

    public String getRegionName() {

        return regionName;

    }

    public void setRegionName(String regionName) {

        this.regionName = regionName;

    }

    public String getParentRegionID() {

        return parentRegionID;

    }

    public void setParentRegionID(String parentRegionID) {

        this.parentRegionID = parentRegionID;

    }

    public Region(String regionID, String regionName, String parentRegionID) {

        super();

        this.regionID = regionID;

        this.regionName = regionName;

        this.parentRegionID = parentRegionID;

    }

    public Region() {

        super();

    }

    @Override

    public String toString() {

        return "Region [regionID=" + regionID + ", regionName=" + regionName + ", parentRegionID=" + parentRegionID

                + "]";

    }

}

package com.hanqi.dao;

import java.util.ArrayList;

import java.util.List;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.Transaction;

import org.hibernate.boot.registry.StandardServiceRegistryBuilder;

import org.hibernate.cfg.Configuration;

import org.hibernate.service.ServiceRegistry;

import com.hanqi.entity.Region;

public class RegionDAO {

    Configuration cfg = null;

    ServiceRegistry sr = null;

    SessionFactory sf =null;

    Session se = null;

    Transaction tr = null;

    public RegionDAO()

    {

        //加载配置文件

        cfg = new Configuration().configure();

        //注册服务

        sr =new StandardServiceRegistryBuilder()

                .applySettings(cfg.getProperties()).build();

    }

    private void init()

    {

        sf = cfg.buildSessionFactory(sr);

        se =sf.openSession();

        tr=se.beginTransaction();

    }

    private void destroy()

    {

        tr.commit();

        se.close();

        sf.close();

    }

    //获取数据列表

    public List<Region> getList(String parentid)

    {

        List<Region> rtn = new ArrayList<Region>();

        init();

        //查询数据

        rtn = se.createQuery("from Region where parentRegionID="+parentid).list();

        destroy();

        return rtn;

    }

}

package com.hanqi.service;

import java.util.List;

import com.hanqi.dao.RegionDAO;

import com.hanqi.entity.Region;

public class RegionService {

    public List<Region> getList(String parentid){

        return new RegionDAO().getList(parentid);

    }

}

package com.hanqi.servlet;

import java.io.IOException;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.alibaba.fastjson.JSONArray;

import com.hanqi.entity.Region;

import com.hanqi.service.RegionService;

/**

 * Servlet implementation class RegionServlet

 */

public class RegionServlet extends HttpServlet {

    private static final long serialVersionUID = 1L;

    /**

     * @see HttpServlet#HttpServlet()

     */

    public RegionServlet() {

        super();

        // TODO Auto-generated constructor stub

    }

    /**

     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)

     */

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        request.setCharacterEncoding("UTF-8");

        response.setCharacterEncoding("UTF-8");

        response.setContentType("text/html");

        //接收参数

        String parentid=request.getParameter("parentid");

        if(parentid!=null)

        {

        //读取地区列表

        List<Region> lr = new RegionService().getList(parentid);

        //返回JSON格式的数据

        String json=JSONArray.toJSONString(lr);

        response.getWriter().print(json);

        }

        else

        {

            response.getWriter().print("[]");

        }

    }

    /**

     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)

     */

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

        // TODO Auto-generated method stub

        doGet(request, response);

    }

}

<!DOCTYPE html>

<html>

<head>

<meta charset="UTF-8">

<title>Insert title here</title>

<!-- 1jQuery的js包 -->

<script type="text/javascript" src="jquery-easyui-1.4.4/jquery.min.js"></script>

<!-- 2css资源 -->

<link rel="stylesheet" type="text/css" href="jquery-easyui-1.4.4/themes/default/easyui.css">

<!-- 3图标资源 -->

<link rel="stylesheet" type="text/css" href="jquery-easyui-1.4.4/themes/icon.css">

<!-- 4easyui的js包 -->

<script type="text/javascript" src="jquery-easyui-1.4.4/jquery.easyui.min.js"></script>

  <!-- 5本地语言包 -->

<script type="text/javascript" src="jquery-easyui-1.4.4/locale/easyui-lang-zh_CN.js"></script>

</head>

<body>

修改

<input class="easyui-combobox" data-options=

"url:'json/combo.json',

valueField:'id',

textField:'text',

editable:false" >

<br>

<br>

省：<input id="sheng" class="easyui-combobox" style="width: 100px" data-options="

url:'RegionServlet?parentid=0',

valueField:'regionID',

textField:'regionName',

onSelect:function(region){

    //alert('选择了省'+region.regionID)

$('#shi').combobox('clear');  //清除原有显示内容

//重新加载

$('#shi').combobox('reload','RegionServlet?parentid='+region.regionID);

$('#quxian').combobox('clear');  //清除原有显示内容

$('#quxian').combobox('reload','RegionServlet');//清除下拉项目

}

" >

市：<input id="shi" class="easyui-combobox" style="width: 100px" data-options="

url:'RegionServlet',

valueField:'regionID',

textField:'regionName',

onSelect:function(region){

    alert('选择了市'+region.regionID)

$('#quxian').combobox('clear');  //清楚原有项目

//重新加载

$('#quxian').combobox('reload','RegionServlet?parentid='+region.regionID);

}

" >

区县：<input id="quxian" class="easyui-combobox" style="width: 100px" data-options="

url:'RegionServlet',

valueField:'regionID',

textField:'regionName'

" >

</body>

</html>