Thymeleaf无法使用表达式“*”绑定表单错误

Question

我使用Spring boot和Thymeleaf模板引擎，并尝试使用th:classappend属性为添加可选的“has error”类

<form method="POST" action="/registration" class="form-signin">
        <h2 class="form-signin-heading">Create your account</h2>

        <div class="form-group" th:classappend="${#fields.hasErrors('*')} ? 'has-error' : ''">
            <input name="username" type="text" class="form-control" placeholder="Username" autofocus="true"/>
            <p class="alert alert-danger" th:if="${#fields.hasErrors('username')}" th:errors="*{username}"></p>
        </div>

        <div class="form-group" th:classappend="${#fields.hasErrors('*')} ? 'has-error' : ''">
            <input name="password" type="text" class="form-control" placeholder="Password" autofocus="true"/>
            <p class="alert alert-danger" th:if="${#fields.hasErrors('password')}" th:errors="*{password}"></p>
        </div>

        <div class="form-group" th:classappend="${#fields.hasErrors('*')} ? 'has-error' : ''">
            <input name="passwordConfirm" type="text" class="form-control" placeholder="Confirm your password" autofocus="true"/>
            <p class="alert alert-danger" th:if="${#fields.hasErrors('passwordConfirm')}" th:errors="*{passwordConfirm}"></p>
        </div>

        <button class="btn btn-lg btn-primary btn-block" type="submit">Submit</button>


    </form>

但是我有这个错误

无法使用表达式“*”绑定表单错误。请检查此表达式是否在适当的上下文中执行（例如，具有th:object属性的a）

我的控制器方法

@RequestMapping(value = "/registration", method = RequestMethod.GET)
    public String registration(Model model) {
        model.addAttribute("userForm", new User());

        return "registration";
    }

    @RequestMapping(value = "/registration", method = RequestMethod.POST)
    public String registration(@ModelAttribute("userForm") User userForm, BindingResult bindingResult, Model model) {
        userValidator.validate(userForm, bindingResult);

        if (bindingResult.hasErrors()) {
            return "registration";
        }

        userService.save(userForm);

        securityService.autologin(userForm.getUsername(), userForm.getPasswordConfirm());

        return "redirect:/welcome";
    }

我做错了什么？

Answer 1

我只是将th:object=“${userForm}属性添加到我的form元素中。现在它工作得很好！