jsp 頁面代碼：table 用div包裹住$("#div_tb table").remove(); 移除div裡面的table 然後再加入table
servlet 與struts2一樣的道理只是配置文件不一樣
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點擊查看struts2寫的級聯下拉框
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>列表</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<script type="text/javascript" src="jquery/jquery-1.9.1.js"></script><!--jquery自己導入-->
<script type="text/javascript" src="jquery/jquery-1.9.1.min.js"></script>
<link rel="stylesheet" type="text/css" href="css/itemListStyle.css"><!--CSS 自己設置-->
<script type="text/javascript">
function getList(){
var sel_val =$("#sel_itemGroup").val();
jQuery.ajax({
url : "getList",
data : {key: sel_val},
type : "post",
cache : false,
dataType : "json",
success:callback
});
}
function callback(json) {
if(json.length==0){
$("#div_tb table").remove();
var new_table="<table id='listTable'>"+
"<tr><td id='td4' width='15%'>序號</td>"+
"<td id='td4' width='25%'>檢測項描述</td>"+
"<td id='td4' width='20%'>傳感器類型</td>"+
"<td id='td4' width='20%'>監測項ID</td>"+
"<td id='td4' width='20%'>操作</td></tr>"+
"<tr><td colspan='5'><font color='red'>"+
"該站點沒有傳感器或者加載數據出錯.....</font></td></tr></table>";
$("#div_tb").append(new_table);
}else{
$("#div_tb table").remove();
var new_table="<table id='listTable'>"+
"<tr><td id='td4' width='15%'>序號</td>"+
"<td id='td4' width='25%'>檢測項描述</td>"+
"<td id='td4' width='20%'>傳感器類型</td>"+
"<td id='td4' width='20%'>監測項ID</td>"+
"<td id='td4' width='20%'>操作</td></tr></table>";
$("#div_tb").append(new_table);
var tb = $("#listTable");
var str ;
for(var i=0;i<json.length;i++){
if(i%2==0){
str = "<tr style='background-color:#D8EFFF'><td>" + (i + 1) + "</td><td>" + json[i].itemName
+ "</td><td>" + json[i].model + "</td><td>"
+ json[i].itemKey + "</td><td>"
+ "<a>刪除</a> | <a>編輯</a>" + "</td></tr>";
}else{
str = "<tr><td>" + (i + 1) + "</td><td>" + json[i].itemName
+ "</td><td>" + json[i].model + "</td><td>"
+ json[i].itemKey + "</td><td>"
+ "<a>刪除</a> | <a>編輯</a>" + "</td></tr>";
}
tb.append(str);
}
}
}
$(function() {
$("#sel_itemGroup").change(getList);
});
</script>
</head>
<body>
<center>
<form id="myform" action="AC86RegisterAction" method="post">
<div>
<table id="listTable1">
<tr>
<td align="left" >
<select class="selectWidth" id="sel_itemGroup">
<option value="1">站點1</option>
<option value="2">站點2</option>
</select>
</td>
</tr>
</table>
</div>
<div id="div_tb" align="center">
<table id="listTable">
<tr>
<td id="td4" width="15%">序號</td>
<td id="td4" width="25%">檢測項描述</td>
<td id="td4" width="20%">傳感器類型</td>
<td id="td4" width="20%">監測項ID</td>
<td id="td4" width="20%">操作</td>
</tr>
</table>
</div>
<br>
<table id="listTable1">
<tr>
<td align="left" >
<select class="selectWidth">
<option>item</option>
</select>
<input type="button" value="添加監測項" >
</td>
</tr>
</table>
</form>
</center>
</body>
</html>
servlet代碼：
package com.sunwe.ems.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONArray;
public class getList extends HttpServlet {
public getList() {
super();
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setHeader("Cache-Control", "no-cache");
response.setContentType("text/json;charset=UTF-8");
response.setCharacterEncoding("utf-8");
String key =request.getParameter("key");
PrintWriter out = response.getWriter();
System.out.println("itemGroupKey "+key);
Item it =new Item();//該對象自己設置
it.setItemKey(8002);
it.setItemGroupKey(1);
it.setItemName("aaa");
it.setModel("dsdsdss");
List<Item> list =new ArrayList<Item>();
list.add(it);
list.add(it);
list.add(it);
list.add(it);
list.add(it);
list.add(it);
list.add(it);
JSONArray json = JSONArray.fromObject(list);
System.out.println(json);
out.print(json);
out.flush();
out.close();
}
}
生成的json格式[{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"},{"id":0,"itemGroupKey":1,"itemKey":8002,"itemName":"aaaa","model":"dsdsdss"}]
xml配置
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">
<servlet>
<description>AJAX</description>
<display-name>AJAX</display-name>
<servlet-name>getList</servlet-name>
<servlet-class>com.sunwe.ems.servlet.getList</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>getList</servlet-name>
<url-pattern>/getList</url-pattern>
</servlet-mapping>
</web-app>
json需要的包
1.commons-lang.jar
2.commons-beanutils.jar
3.commons-collections.jar
4.commons-logging.jar
5.ezmorph.jar
6.json-lib-2.2.2-jdk15.jar
json包下載：
免費下載地址在 http://linux.linuxidc.com/
用戶名與密碼都是www.linuxidc.com
具體下載目錄在 /2014年資料/4月/28日/jQuery Ajax Servlet JSON（Struts2）動態生成table
下載方法見 http://www.linuxidc.com/Linux/2013-07/87684.htm
jQuery 的詳細介紹：請點這裡
jQuery 的下載地址：請點這裡