springmvc 后台接收前台数据

1,使用HttpServletRequest获取

1.1后台方法

    @RequestMapping(value="/login",method = RequestMethod.POST)    public String login(HttpServletRequest request) {        if(userService.selectUser(request.getParameter("username"),request.getParameter("password"))!=null)        {            return "index";        }        else            return "login";    }

1.2前台表单的name属性要和后台参数名保持一致

     <form action="mavenTest/user/login" method="post">            <input type="text" name="username"  placeholder="Username...">            <input type="password" name="password"  placeholder="Password...">             <button type="submit" class="btn">Sign in!</button>      </form>

2.自动注入bean属性

2.1后台方法

    @RequestMapping(value="/login",method = RequestMethod.POST)    public String login(User user) {        if(userService.selectUser(user.getUsername(),user.getPassword())!=null){            return "index";        }        else            return "login";    }

2.2前台表单的name属性要和类的参数名保持一致，并且要有相应的get和set方法

user类

public class User implements Serializable{    private int id;    private String username;    private String password;    private int age;

     <form action="mavenTest/user/login" method="post">            <input type="text" name="username"  placeholder="Username...">            <input type="password" name="password"  placeholder="Password...">             <button type="submit" class="btn">Sign in!</button>      </form>