Question

我有这样的控制器：

@Controller
public class AuthController {

private final Logger logger= LoggerFactory.getLogger(AuthController.class);

private UserService userService;

public AuthController(UserService userService) {
    this.userService = userService;
}

@GetMapping("login")
public String login(){
    return "auth/login";
}
@GetMapping("/profile")
public String profile(){
    return "auth/profile";
}
@GetMapping("/register")
public String register(Model model){
    model.addAttribute("user",new User());
    model.addAttribute("success",false);
    return "auth/register";
}
@PostMapping("/register")
public String registerNewUser(@Valid User user, BindingResult bindingResult, Model model, RedirectAttributes redirectAttributes){
    if(bindingResult.hasErrors()){
        //show validation errors
        logger.warn("Validation errors were found while registering a new user");
        model.addAttribute("user",user);
        model.addAttribute("validationErrrs",bindingResult.getAllErrors());
        return "auth/register";
    }else{
        User newUser = userService.register(user);
        redirectAttributes
                .addAttribute("id",newUser.getId())
                .addFlashAttribute("success",true);
        logger.info("No validation errors were found while registerning a new user");
        return "redirect:/register";
    }
}
@GetMapping("/activate/{email}/{activationCode}")
public String activate(@PathVariable String email, @PathVariable String activationCode) {
    Optional<User> user = userService.findByEmailAndActivationCode(email,activationCode);
    if( user.isPresent() ) {
        User newUser = user.get();
        newUser.setEnabled(true);
        newUser.setConfirmPassword(newUser.getPassword());
        userService.save(newUser);
        userService.sendWelcomeEmail(newUser);
        return "auth/activated";
    }
    return "redirect:/";
 }
 }

我调用方法registerNewUser，并且我的记录器始终显示有关“注册新用户时未发现验证错误”的信息，因为执行了body。因此，我认为redirectAttributes.addFlashAttribute（“ success”，true）;应该可以正常工作。不幸的是，当我返回“ redirect：/ register”时，我得到了新的视图，但没有根据“ succes”属性来表示。这是我的视图代码的一部分：

<div class="row" th:if="${success}">
<div class="col-md-3"></div>
<div class="col-md-6 alert alert-success" role="alert" >
    You have successfully registered with us. Please check your email to 
activate your account.
</div>
<div class="col-md-3"></div>
</div>

<!-- User Registration form -->
<form class="form-horizontal" role="form" method="POST" 
th:action="@{/register}" th:object="${user}" th:if="!${success}">
<div class="row">

有人可以帮助我查明缺少警报的原因吗？

Answer 1

您将在registerNewUser()内重定向到GET /register。这将调用以下方法：

@GetMapping("/register")
public String register(Model model){
    model.addAttribute("user",new User());
    model.addAttribute("success",false);
    return "auth/register";
}

在这种方法中，您要添加模型属性success，并将其设置为false，从而有效地覆盖重定向属性。

由于使用RedirectAttributes来填充重定向目标的Model，因此您可以将model.addAttribute(..)调用包装在if语句中。例如：

@GetMapping("/register")
public String register(Model model){
    model.addAttribute("user",new User());
    if (!model.containsAttribute("success")) {
        model.addAttribute("success",false);
    }
    return "auth/register";
}

或者，您可以保留model属性，因为解析器足够聪明，可以在丢失${success}到false时对其进行评估。例如：

@GetMapping("/register")
public String register(Model model){
    model.addAttribute("user",new User());
    return "auth/register";
}

为什么@PostMapping不会改变th：if

1 个答案: