Question

SpringMvc如何获得前台传来的值

Answer 1

1. 通过HttpServletRequest

   public String toIndex(HttpServletRequest request){

   //获得前台name为username的元素的值
   

   System.out.println(request.getParameter("username"));
   return "index";
   

   }

2. 通过参数名获得

   @RequestMapping(value="/index")
   public String   toIndex(String username){      //这里名字要与前端元素名字一致才能获得
   System.out.println(username);
   return "index";
   }

3. 通过@RequestParam注解获得

   @RequestMapping(value="/index")
   public String toIndex(@RequestParam(value="username",required=false)String username111){  //username要与前端一致，在此处可以理解为参数username111的别名
   System.out.println(username111);
   return "index";
   }

4. SpringMvc还能通过将vo作为参数获得vo的各个属性
   @RequestMapping(value="/index")
   public String toIndex(User user){
   System.out.println(user.getUserName());
   System.out.println(user.getPassword());
   return "index";