这篇文章主要为大家详细介绍了Ajax实现省市县三级联动，文中示例代码介绍的非常详细，具有一定的参考价值，感兴趣的小伙伴们可以参考一下
本文实例为大家分享了Ajax实现省市县三级联动的具体代码，供大家参考，具体内容如下
首先建立数据库，如下所示
接口
省
import java.util.List; public interface ProvinceDao { List findAll(); } 市
import java.util.List; public interface CityDao { List findCityByPid(int pid); } 县
import java.util.List; public interface AreaDao { List findAreaByCid(int cid); }接口实现类
省
import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; public class ProvinceDaoImpl implements ProvinceDao{ public List findAll(){ Connection conn = DBHelper.getConn(); ArrayList provinces = new ArrayList(); String sql = "select * from aprovince"; try { PreparedStatement ps = conn.prepareStatement(sql); ResultSet rs = ps.executeQuery(); while (rs.next()){ Province p = new Province(); p.setPid(rs.getInt(1)); p.setPname(rs.getString(2)); provinces.add(p); } } catch (SQLException e) { e.printStackTrace(); } return provinces; } } 市
import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; public class CityDaoImpl implements CityDao { @Override public List findCityByPid(int pid) { Connection conn = DBHelper.getConn(); ArrayList cities = new ArrayList<>(); String sql = "select * from acity where pid=?"; try { PreparedStatement ps = conn.prepareStatement(sql); ps.setInt(1,pid); ResultSet rs = ps.executeQuery(); while (rs.next()){ City city = new City(); city.setPid(rs.getInt(3)); city.setCid(rs.getInt(1)); city.setCname(rs.getString(2)); cities.add(city); } } catch (SQLException e) { e.printStackTrace(); } return cities; } } 县
import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; public class AreaDaoImpl implements AreaDao { @Override public List findAreaByCid(int cid) { Connection conn = DBHelper.getConn(); ArrayList areas = new ArrayList<>(); String sql = "select * from aarea where cid=?"; try { PreparedStatement ps = conn.prepareStatement(sql); ps.setInt(1,cid); ResultSet rs = ps.executeQuery(); while (rs.next()){ Area area = new Area(); area.setCid(rs.getInt(3)); area.setAid(rs.getInt(1)); area.setAname(rs.getString(2)); areas.add(area); } } catch (SQLException e) { e.printStackTrace(); } return areas; } }servlet
省
package cn.zhc.servlet; import cn.zhc.dao.Impl.ProvinceDaoImpl; import cn.zhc.dao.ProvinceDao; import cn.zhc.domin.Province; import com.alibaba.fastjson.JSONObject; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.List; @WebServlet("/findAll") public class FindAll extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=utf-8"); ProvinceDao provinceDao = new ProvinceDaoImpl(); List lists=provinceDao.findAll(); response.getWriter().write(JSONObject.toJSONString(lists)); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doPost(request, response); } } 市
package cn.zhc.servlet; import cn.zhc.dao.CityDao; import cn.zhc.dao.Impl.CityDaoImpl; import cn.zhc.domin.City; import com.alibaba.fastjson.JSONObject; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.util.List; @WebServlet("/findCityByPid") public class FindCityByPid extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=utf-8"); String pid = request.getParameter("pid"); CityDao cityDao = new City以上就是Ajax实现省市县三级联动的详细内容，更多请关注易知道|edz.cc其它相关文章！
