SpringMVC中的参数绑定总结的7种方式

迈不过友情╰ 2022-04-18 05:53 99阅读 0赞

spring mvc封装数据的对象有HttpSession、HttpServletRequest、HttpServletResponse、ModelAndView、ModelMap、Model、Map

Map map,Model model,ModelMap modelmap,ModelAndView mav,HttpServletRequest request 声明变量 
    request.getSession().setAttribute("test", "hello spring mvc!"); 
    request.setAttribute("test", "hello spring mvc!"); 
    mav.addObject("test","hello spring mvc!");
    modelmap.addAttribute("test", "hello spring mvc!"); 
    model.addAttribute("test", "hello spring mvc!"); 
    map.put("test","hello spring mvc!");

在跳转页面可以通过$\{test\}方式取值，优先取Map、Model和ModelMap的，Map、Model和ModelMap是同一个东西，谁最后赋值的就取谁的，然后是request，最后是从session中获取  
假如想直接取request.getParameter("test"),则用$\{param.test\}

@Controller
    //0.使用Session在回话中传递参数
    @SessionAttributes(value="message")
    public class IndexController{
            //1.使用request获取页面数据，并传递给跳转页面
    	@RequestMapping(value="index1")
    	public String hello1(HttpServletRequest request) {
    		String s1=request.getParameter("userName");
    		System.out.println(s1);
    		request.setAttribute("message", s1);
    		
    		return "hello";
    	}
    
            //2.使用ModelAndVies包装返回页面数据
    	@RequestMapping(value="index2")
    	public ModelAndView hello2(String userName) {
    		System.out.println(userName);
    		ModelAndView mav=new ModelAndView("hello");
    		mav.addObject("message", userName);
    		return mav;
    	}
    	
            //3.使用ModelMap包装返回页面数据
    	@RequestMapping(value="index3")
            //@RequestParam("userName")String name  接收的参数为userName,为其起名为name
    	public String hello3(@RequestParam("userName")String name,ModelMap mm) {
    		System.out.println(name);
    		String s3=name;
    		mm.addAttribute("message", s3);
    		return "hello";
    	}
    
            //4.使用Model包装返回页面数据
    	@RequestMapping(value="index4")
            //@RequestParam("userName")String name  接收的参数为userName,为其起名为name
    	public String hello4(@RequestParam("userName")String name,Model model) {
    		System.out.println(name);
    		String s3=name;
    		model.addAttribute("message", s3);
    		return "hello";
    	}
    	
            //5.使用Map包装返回页面数据
    	@RequestMapping(value="index5")
    	public String hello5(String userName,Map map) {
    		System.out.println(userName);
    		String s4=userName;
    		map.put("message", s4);
    		return "hello";
    	}
    
            //6.使用Map包装对象
    	@RequestMapping(value="index6")
    	public String hello6(userInfo userinfo,Map map) {
    		System.out.println(userinfo);
    		Date date=new Date();
    		userinfo.setDate(date);
    		map.put("message", userinfo);
    		return "hello";
    	}
    	
            //7. 测试返回页面取值对Map、Model、ModelMap、ruquest、session的设值的先后
    	@RequestMapping(value="index7")
    	public String hello7(HttpServletRequest request,HttpServletResponse response,Map map,Model model,ModelMap mm) {
    		String s1=request.getParameter("userName");
    		
    		mm.addAttribute("message", "天明mm");
    		model.addAttribute("message", "天明model");
    		map.put("message","天明map");
    		request.setAttribute("message", s1);
    		
    		return "hello";
    	}
    }