ComboBox（下拉列表框）实现省、市、县三级联动,用hibernate连接数据库

ComboBox（下拉列表框）实现省、市、县三级联动,用hibernate连接数据库
```
package com.hanqi.web;

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");
        // 接受参数
        String parentid =request.getParameter("parentid");
        if(parentid!=null)
        {
        //地区地区列表
        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);
    }

}
```
html文件：

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>

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

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

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

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


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

</head>
<body>
修改员工的页面

<input id="cc1" class="easyui-combobox" data-options="
valueField: 'id',
textField: 'text',
url:'json/combo.json',
onSelect: function(rec){
var url = 'json/combo1.json?id='+rec.id;
$('#cc2').combobox('reload', url);
}"/>
<input id="cc2" class="easyui-combobox" data-options="valueField:'id',textField:'text'" />
<br><br>
省：
<input id="sheng" class="easyui-combobox" style="100px"
data-options="{
url:'RegionServlet?parentid=0',
valueField:'regionID',
textField:'regionName',
onSelect:function(region){
//alert('选择了省id='+region.regionID);
//清除原有项目
$('#shi').combobox('clear');
$('#quxian').combobox('clear');
//重新加载
$('#shi').combobox('reload','RegionServlet?parentid='+region.regionID);
$('#quxian').combobox('reload','RegionServlet');
}
}">
市：
<input id="shi" class="easyui-combobox" style="100px"
data-options="{
url:'RegionServlet',
valueField:'regionID',
textField:'regionName',
onSelect:function(region){
$('#quxian').combobox('clear');
//重新加载
$('#quxian').combobox('reload','RegionServlet?parentid='+region.regionID);

}
}">

区/县：
<input id="quxian" class="easyui-combobox" style="100px"
data-options="{
url:'RegionServlet',
valueField:'regionID',
textField:'regionName'
}">
</body>
</html>

上图：

源码先不写了，如有需要加我qq：289326698
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原文地址：https://www.cnblogs.com/diaozhaojian/p/6108881.html