​

前端：

<!--用table布局、 label的inline-block 对齐input-->
<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8" />
    <title>Title</title>
</head>
<body>
<div class="web_login">
    <ul>
        <ul>
            <!--accept-charset 属性规定服务器处理表单数据所接受的字符集.此属性的默认值是
            "unknown"，表示表单的字符集与包含表单的文档的字符集相同-->
            <form name="form2" accept-charset="utf-8"  action="/security/addregister" method="post">
                <!--用table对齐-->
                <table >
                    <tr>
                        <td>用户名：</td>
                        <td><input type="text" name="username" maxlength="16"/></td>
                    </tr>
                    <tr>
                        <td>密码：</td>
                        <td><input type="password" name="password1" maxlength="16" /></td>
                    </tr>
                    <tr>
                        <td>确认密码：</td>
                        <td><input type="password" name="password2" maxlength="16" /></td>
                    </tr>
                </table>

                <div class="inputArea">
                    <a th:href="@{/security/readdoc}" target="_blank">阅读注册协议</a>
                    <input type="submit" value="同意协议并注册"/>
                </div>
            </form>
        </ul>
    </ul>
</div>
</body>
</html>


 

后端：



@RequestMapping("/addregister")
    public String register(HttpServletRequest request){
        String username = request.getParameter("username");
        String password1 = request.getParameter("password1");
        String password2 = request.getParameter("password2");
        if (password1.equals(password2))
        {
            User1 user = new User1();
            user.setUserName(username);
            user.setUserPwd(password1);
            userService.addUser(user);
            return "login";
        }
        else
        {
            return "register";
        }
    }


 

二、form提交： 



<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
  <meta charset="UTF-8">
  <title>课程管理系统登录页面</title>
  <link rel="stylesheet" type="text/css" th:href="@{/css/style.css}" />
  <script type="text/javascript" th:src="@{/js/jquery-3.1.1.min.js}"></script>
</head>
<body>
<div>
  <div id="wrapper" style="text-align:center">
    <img id="login"   width="100" height="20"   th:src="@{/pics/logo.png}" />
    <div id="f_title">课程管理系统用户登录</div>
    <!--${user}取后台转递的map参数，其中有个key是user-->
    <form th:action="@{/security/login}" method="post" th:object="${user}">
      <div  class="f_row">
        <span>用户姓名:</span>
        <input type="text" class="form-control" name="userName" th:value="*{userName}" placeholder="请输入姓名">
      </div>
      <div class="f_row">
        <span>登录密码:</span>
        <input type="text" class="form-control" name="userPwd" th:value="*{userPwd}" placeholder="请输入密码">
      </div>
      <br>
      <div class="f_row">
        <input type="submit" value=" 登 录 "></input>
      </div>
    </form>
  </div>
</div>
<div id="footer">
  <div th:insert="footer :: copy"></div>
  <div th:insert="footer :: time"></div>
</div>
</body>
</html>


前端向后端传递数据_css

 

 登录，执行到控制器：/security/login



@PostMapping(value="/login")
    public String login( User1 user,Map<String, Object> map ) {
        String userName=user.getUserName();
        String userPwd=user.getUserPwd();
        List<User1> lus=userService.loadUserByUserName(userName);
        if(lus!=null){
            User1 user1=lus.get(0);
            if(user1.getUserPwd().equals(userPwd))
            {
                map.put("user",user1);
                return "main";
            }
        }
        return "login";
    }


两个参数都收到数据？？

user的值：

前端向后端传递数据_css_02

 

 

map的值：

前端向后端传递数据_css_03

 

如果将参数改为：

前端向后端传递数据_html_04

 

则map收不到数据。