dwr实现三联动

最新推荐文章于 2022-06-20 19:03:35 发布

imti_cg

最新推荐文章于 2022-06-20 19:03:35 发布

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分类专栏： ajax 文章标签： DWR Java SQL Microsoft JDBC

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[b]web.xml配置：[/b]

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4"
	xmlns="http://java.sun.com/xml/ns/j2ee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
	<display-name>DWR</display-name>
	<servlet>
		<servlet-name>dwr-invoker</servlet-name>
		<servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class>
		<init-param>
			<param-name>debug</param-name>
			<param-value>true</param-value>
		</init-param>
	</servlet>

	<servlet-mapping>
		<servlet-name>dwr-invoker</servlet-name>
		<url-pattern>/dwr/*</url-pattern>
	</servlet-mapping>

	<welcome-file-list>
		<welcome-file>index.html</welcome-file>
		<welcome-file>index.htm</welcome-file>
		<welcome-file>index.jsp</welcome-file>
		<welcome-file>default.html</welcome-file>
		<welcome-file>default.htm</welcome-file>
		<welcome-file>default.jsp</welcome-file>
	</welcome-file-list>
</web-app>

[b]dwr.xml文件：[/b]

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://getahead.org/dwr/dwr20.dtd">
<dwr>
	<allow>
		<create creator="new" javascript="AjaxDAO">
			<param name="class" value="com.soft.dwr.AjaxDAO" />
		</create>
    </allow>
</dwr>

java类：
DataSourceFactory.java

package com.soft.dwr;


import org.apache.commons.dbcp.BasicDataSource;


public class DataSourceFactory {

	/**
	 * @param args
	 */
	static BasicDataSource  ds;//apatch的连接池
	public static BasicDataSource getDataSource(){
		if(ds==null){
			ds=new BasicDataSource();
			ds.setDriverClassName("com.microsoft.jdbc.sqlserver.SQLServerDriver");
			ds.setUrl("jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=DWR");
			ds.setUsername("sa");
			ds.setPassword("");
			ds.setMaxActive(5);
		}
		return ds;
	}

}

AjaxDao.java

package com.soft.dwr;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.Map;

public class AjaxDAO {

	private final String COUNTRY = "select * from country";
	private final String PROVINCE = "select * from province where countryid=?";
	private final String CITY="select * from city where provinceid=?";


	public  Map getProvince(int id) {
		Map<String, String> map = new HashMap<String, String>();
		Connection con;
		try {
			con = DataSourceFactory.getDataSource().getConnection();
			PreparedStatement ps = con.prepareStatement(PROVINCE);
			ps.setInt(1, id);
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				map.put(new Integer(rs.getInt(1)).toString(), rs.getString(2));
			}
                   if(rs!=null){rs.close()}
                   if(ps!=null){ps.close()}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return map;

	}

	public Map getCountry() {
		Map<String, String> map = new HashMap<String, String>();
		Connection con;
		try {
			con = DataSourceFactory.getDataSource().getConnection();
			PreparedStatement ps = con.prepareStatement(COUNTRY);
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				map.put(new Integer(rs.getInt(1)).toString(), rs.getString(2));
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return map;

	}

	public  Map getCity(int id) {
		Map<String, String> map = new HashMap<String, String>();
		Connection con;
		try {
			con = DataSourceFactory.getDataSource().getConnection();
			PreparedStatement ps = con.prepareStatement(CITY);
			ps.setInt(1, id);
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				map.put(new Integer(rs.getInt(1)).toString(), rs.getString(2));
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		return map;

	}
}

[b]页面：[/b]

<%@ page language="java" contentType="text/html; charset=UTF-8"
	pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script type='text/javascript' src='/ajax/dwr/interface/AjaxDAO.js'></script>
<script type='text/javascript' src='/ajax/dwr/engine.js'></script>
<script type='text/javascript' src='/ajax/dwr/util.js'></script>

<script>
function init(){

   AjaxDAO.getCountry(callback);
}
function callback(data){

  var country=document.getElementById("country");
  DWRUtil.removeAllOptions(country);
  DWRUtil.addOptions(country,{'':'请选择'});
  DWRUtil.addOptions(country,data);
}

function getProvince(value){
if(value!='')
AjaxDAO.getProvince(parseInt(value),setProvince);
}

function setProvince(data){
 var province=document.getElementById("province");
  DWRUtil.removeAllOptions(province);
  DWRUtil.addOptions(province,{'':'请选择'});
  DWRUtil.addOptions(province,data);
}

function getCity(value){
if(value!='')
AjaxDAO.getCity(parseInt(value),setCity);
}

function setCity(data){
 var city=document.getElementById("city");
  DWRUtil.removeAllOptions(city);
  DWRUtil.addOptions(city,{'':'请选择'});
  DWRUtil.addOptions(city,data);
}

</script>
</head>
<body onload="init()" >
<select id="country" onchange="getProvince(this.value)">
</select>
<select id="province" onchange="getCity(this.value)">
</select>
<select id="city">
</select>
</body>
</html>

关于数据库自己设置：