后台将数据传回前台的三种绑定的方式(Model,Map.ModelAndView)

Posted 2022-06-21 qingmuchuanqi48

//方式1：通过model 将数据绑定
    @RequestMapping(value = "findByIdModel", method = RequestMethod.GET)
    public String findByIdModel(@RequestParam("empno") int id, Model model) 
        
        Emp emp = empService.findById(id);//从业务层传回的数据
        
        model.addAttribute("emp", emp);//将数据绑定
        
        return "findbyid";//返回的页面
    
//方式2：通过Map 
    @RequestMapping(value = "findByIdMap", method = RequestMethod.GET)
    public String findByIdMap(@RequestParam("empno") int id, Map<String,Object> map) 
        
        Emp emp = empService.findById(id);
        
        map.put("emp", emp);
        
        return "findbyid";
    
    
    //方式3：通过ModelAndView
    @RequestMapping(value = "findByIdMAV", method = RequestMethod.GET)
    public ModelAndView findByIdMAV(@RequestParam("empno") int id) 
        
        Emp emp = empService.findById(id);
        
//        ModelAndView mav = new ModelAndView("findbyid");
        ModelAndView mav = new ModelAndView();
        
        mav.setViewName("findbyid");//设置返回页面
        
        mav.addObject("emp", emp);//设置action传递的值
        
        System.out.println("use ModelAndView:"+emp);
        
        return mav;