SpringMVC学习笔记（六）：如何返回数据

来源：互联网发布：中国家居建材知乎编辑：程序博客网时间：2024/06/08 06:15

以下为4种返回数据的方式，听说第三种最为常用。
控制器：

package com.lin.controller;import java.io.UnsupportedEncodingException;import java.util.Map;import javax.servlet.http.HttpServletRequest;import org.springframework.stereotype.Controller;import org.springframework.ui.Model;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.servlet.ModelAndView;@Controller@RequestMapping("/user")public class ReturnDataServlet {    //参数返回第一种方式 HttpServletRequest    @RequestMapping("/add1.do")    public String add1(HttpServletRequest req){        String username = req.getParameter("username");//这段代码传回的username中文乱码，但是加上ModelView就不会了        String password = req.getParameter("password");        String str = username + "----" + password;        System.out.println(str);        req.setAttribute("up", str);        return "index";    }    //参数返回第二种方式ModelAndView    @RequestMapping("/add2.do")    public ModelAndView add2(){        ModelAndView mav = new ModelAndView("index");        mav.addObject("username", "老哥");        mav.addObject("password", "稳");        return mav;    }    //参数返回第三种方式Model    @RequestMapping("/add3.do")    public String add3(Model model){        model.addAttribute("username", "老铁");        model.addAttribute("password", "稳");        return "index";    }    //参数返回第四种方式 Map    @RequestMapping("/add4.do")    public String add4(Integer password,Map map){        System.out.println(map.get("password"));        map.put("username", "老司机");        map.put("password", "稳");        return "index";    }}

前端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>    <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">    <!--    <link rel="stylesheet" type="text/css" href="styles.css">    -->  </head>  <body>    <form action="user/add1.do">        username:<input type="text" name="username"/><br>        password:<input type="text" name="password"/><br>        <input type="submit" value="方式一"/>    </form>    <h3>${up }</h3>    <hr>    <form action="user/add2.do">        <input type="submit" value="方式二"/>    </form>    <hr>    <form action="user/add3.do">        <input type="submit" value="方式三"/>    </form>      <hr>       <form action="user/add4.do">        <input type="submit" value="方式四"/>    </form>    <h3>${username }---${password }</h3>      <hr>  </body></html>

其他的配置和过滤器与前面的是一样。

阅读全文

0 0