java前后端传值

一后端发

@RequestMapping("/test")
public ModelAndView testUser(){
    ModelAndView model = new ModelAndView();
    model.setViewName("user");
    User user = new User();
    user.setId(28);
    user.setName("laozhang");
    model.addObject("user",user);
    return model;
}

前端接

user.jsp ：${user.name}${user.id}

二后端发

@RequestMapping(value = "/test")      //    ,method = RequestMethod.POST) 限制只接受post请求
public String testUser(ModelMap modelMap ){
        User user = new User();
        user.setId(28);
        user.setName("laozhanglai");

	modelMap.addAttribute("user",user);

return "user" ; //重定向 redirect //return "redirect:/user/demo";}

前端接

user.jsp ：${user.name}${user.id}

三后端接

@RequestMapping("/test/{id}/{name}")     //获取前端get请求
public String testUser(ModelMap modelMap, @PathVariable ("id") Integer sid,@PathVariable ("name")String sname){

@RequestMapping("/test/{id}/{name}")     //获取前端get请求
public String testUser(ModelMap modelMap, @PathVariable Integer id,@PathVariable String name){

前端发

localhost:8080/test/4/laowang

四后端接

@RequestMapping("/test")     //获取post请求
public String testUser(ModelMap modelMap,HttpServletRequest request){
	String id = request.getParameter("id");
        String name = request.getParameter("name");

}

@RequestMapping("/test")   //直接获取id  name  赋值个User类实例
public String testUser(ModelMap modelMap,User user){

}

@RequestMapping("/test")
@ResponseBody
public User testUser(User user){

 	int id = user.getId();
        string name = user.getName();
        return "success";

}

前端发

method="post" action="/test">
    type="text" name="id"/>
    type="text" name="name"/>
    type="submit" value="提交"/>

五后端发

@RequestMapping("/test")
@ResponseBody   //申明调用spring-mvc.html配置的Json,向前端输出Json
public User testUser(){
    User user = new User();
    user.setId(28);
    user.setName("laowang");
    return user;

}

前端接

收到json格式数据{"id":28,"name":"laowang"}

六后端接

@RequestMapping("/test")
public String testUser(@RequestBody User user){
        int id = user.getId();
        string name = user.getName();
        return "success";

}

前端发

发json格式数据{"id":28,"name":"laowang"}