让我苦苦寻找的那段代码---springmvc的ajax前后台交互

导入jar包:

web.xml

   <servlet>
       <servlet-name>spmvc</servlet-name>
       <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
       <load-on-startup>1</load-on-startup>
   </servlet>
   <servlet-mapping>
       <servlet-name>spmvc</servlet-name>
       <url-pattern>*.do</url-pattern>
   </servlet-mapping>

在web.xml同级目录下建立spmvc-servlet.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:p="http://www.springframework.org/schema/p"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:mvc="http://www.springframework.org/schema/mvc"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xsi:schemaLocation="
         http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans.xsd
         http://www.springframework.org/schema/context
         http://www.springframework.org/schema/context/spring-context.xsd
         http://www.springframework.org/schema/mvc
         http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
         http://www.springframework.org/schema/tx
         http://www.springframework.org/schema/tx/spring-tx.xsd
         http://www.springframework.org/schema/aop
         http://www.springframework.org/schema/aop/spring-aop.xsd">
 <context:component-scan base-package="controller" />
 <context:annotation-config />
 <mvc:annotation-driven />
 </beans>

实体类User.java

 package Model;

 public class User {
     private int id;
     private String username;
     private int age;
     public int getId() {
         return id;
     }
     public void setId(int id) {
         this.id = id;
     }
     public String getUsername() {
         return username;
     }
     public void setUsername(String username) {
         this.username = username;
     }
     public int getAge() {
         return age;
     }
     public void setAge(int age) {
         this.age = age;
     }

 }

Action代码:

 package controller;

 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

 import javax.servlet.http.HttpServletRequest;

 import org.json.JSONException;
 import org.json.JSONObject;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.ResponseBody;

 import Model.User;

 @Controller
 @RequestMapping("/user")
 public class DemoController {
     @RequestMapping(value="/list",method=RequestMethod.GET)
     @ResponseBody
     public Map<String, Object> getUserList(){
         List<User> list=new ArrayList<User>();
         User user=new User();
         user.setId(1);
         user.setUsername("guoyansi");
         user.setAge(25);
         list.add(user);
         Map<String, Object> map=new HashMap<String, Object>(3);
         map.put("total", 1);
         map.put("data", list);
         map.put("success", "true");
         return map;
     }

     @RequestMapping(value="/add1",method=RequestMethod.POST)
     @ResponseBody
     public Map<String, String> addUser1(@RequestBody User user){
         /**
          * 这种实体类参数的接受  只能接受ajax发送过来的json字符串
          */
         Map<String, String> map=new HashMap<String, String>(1);
         System.out.println(user.getUsername());
         map.put("success", "true");
         return map;
     }    

     @RequestMapping(value="/add2",method=RequestMethod.POST)
     @ResponseBody
     public Map<String, String> addUser2(HttpServletRequest request){
         String data=request.getParameter("data");
         JSONObject json=null;
         try {
             json=new JSONObject(data);
             System.out.println(json.getString("username"));
         } catch (JSONException e) {
             e.printStackTrace();
         }
         Map<String, String> map=new HashMap<String, String>(1);
         map.put("success", "true");
         return map;
     }    

     @RequestMapping(value="/add3",method=RequestMethod.POST)
     @ResponseBody
     public Map<String, String> addUser3(HttpServletRequest request){
         String username=request.getParameter("username");
         System.out.println(username);
         Map<String, String> map=new HashMap<String, String>(1);
         map.put("success", "true");
         return map;
     }
 }

index.jsp

 <%@ 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>My JSP 'index.jsp' starting page</title>
 <script type="text/javascript" src="js/jquery-1.7.2.min.js"></script>
 <script type="text/javascript">
 $(function(){
     $.ajax({
         type:"GET",
         contentType:"application/json",
         url:"user/list.do",
         dataType:"json",
         success:function(data){
             //alert(data);
             //data=eval("("+data+")");
             if(data&&data.success=="true"){
                 $("#info").html("共"+data.total+"条数据.<br/>");
                 $.each(data.data,function(i,item){
                     $("#info").append("编号:"+item.id+",姓名:"+item.username+",年龄:"+item.age);
                 });
             }
             else{
                 alert("获取数据有异常");
             }
         },
         error:function(){
             alert("提交失败!!!!!");
         }
     });

     $("#submit1").click(function(){
         var data={};
         data.id=Number($("input[name=id]").val());
         data.username=$("input[name=username]").val();
         data.age=Number($("input[name=age]").val());
         $.ajax({
             type:"POST",
             data:JSON.stringify(data),
             url:"user/add1.do",
             contentType:"application/json",
             dataType:"json",
             success:function(data){
                 if(data&&data.success=="true"){
                     alert("添加成功!!!");
                 }
                 else{
                     alert("添加失败!!!");
                 }
             },
             error:function(){
                 alert("提交失败!!!!");
             }
         })
     });

     $("#submit2").click(function(){
         var data={};
         data.id=Number($("input[name=id]").val());
         data.username=$("input[name=username]").val();
         data.age=Number($("input[name=age]").val());
         $.ajax({
             type:"POST",
             data:"data="+JSON.stringify(data),
             url:"user/add2.do",
             //contentType:"application/json",
             dataType:"json",
             success:function(data){
                 if(data&&data.success=="true"){
                     alert("添加成功!!!");
                 }
                 else{
                     alert("添加失败!!!");
                 }
             },
             error:function(){
                 alert("提交失败!!!!");
             }
         })
     });

     $("#submit3").click(function(){
         var data="";
         data+="id="+$("input[name=id]").val();
         data+="&username="+$("input[name=username]").val();
         data+="&age="+$("input[name=age]").val();
         data+="&gg=tt=5";
         $.ajax({
             type:"POST",
             data:data,
             url:"user/add3.do",
             //contentType:"application/json",
             dataType:"json",
             success:function(data){
                 if(data&&data.success=="true"){
                     alert("添加成功!!!");
                 }
                 else{
                     alert("添加失败!!!");
                 }
             },
             error:function(){
                 alert("提交失败!!!!");
             }
         })
     });

 })
 </script>
 </head>

 <body>
     编号：<input type="text" name="id" />
     姓名：<input type="text" name="username" />
     年龄：<input type="text" name="age" />
     <input type="button" value="发送json字符串,后台可以用实体类接受" id="submit1" />
     <input type="button" value="发送含有=和json字符串数据到后台," id="submit2" />
     <input type="button" value="发送普通数据到后台," id="submit3" />
     <hr />
     <div id="info"></div>
 </body>
 </html>