BindingResult 和 Bean 名称的纯目标对象'phonebook'都不能用作请求属性

Question

我试图为电话号码输入添加验证，但我在访问索引时坚持解决此错误。

错误消息

由以下原因引起：org.attoparser.ParseException：执行期间出错 处理器 'org.thymeleaf.spring5.processor.SpringInputGeneralFieldTagProcessor' (模板："索引" - 第 76 行，第 73 行(

原因：java.lang.IllegalStateException：既不是 BindingResult 也不是 Bean 名称"电话号码"的纯目标对象可作为请求提供 属性

索引.html

<div class="myForm">
<form th:action="@{/save}"  method="post" th:object="${phonebook}">
<div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel" aria-hidden="true">
<div class="modal-dialog" role="document">
<div class="modal-content">
<div class="modal-header">
<h5 class="modal-title" id="exampleModalLabel">Update or Create</h5>
<button type="button" class="close" data-dismiss="modal" aria-label="Close">
<span aria-hidden="true">&times;</span>
</button>
</div>
<div class="modal-body">
<div class="form-group">
<input type="hidden" class="form-control" id="id" name="id" value=""/>
</div>
<div class="form-group">
<label for="surname" class="col-form-label">Surname:</label>
<input type="text" class="form-control" id="surname" name="surname" value=""/>
</div>
<div class="form-group">
<label for="firstname" class="col-form-label">First Name:</label>
<input type="text" class="form-control" id="firstname" name="firstname" value=""/>
</div>
<div class="form-group">
<label for="phonenumber" class="col-form-label">Phone Number:</label>
<input type="text" class="form-control" th:field="*{phonenumber}" id="phonenumber" name="phonenumber" value=""/>
<span th:if="${#fields.hasErrors('phonenumber')}" class="help-block" th:errors="*{phonenumber}"></span>
</div>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
<input type="submit" class="btn btn-primary" value="Save"/>
</div>
</div>
</div>
</div>
</form>

控制器

@RequestMapping(value = {"/"}, method = RequestMethod.GET)
public String showPage(Model model, @RequestParam(defaultValue = "0") int page) {
model.addAttribute("data", phonebookRepository.findAll(PageRequest.of(page, 10)));
model.addAttribute("currentPage", page);
return "index";
}
@PostMapping("/save")
public String save(@Valid Phonebook p, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
return "redirect:/";
}else {
phonebookRepository.save(p);
}
return "redirect:/";
}

电话簿

@Entity
@Table(name = "Phonebook")
public class Phonebook {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id")
private Integer id;
@NotNull
@Size(max=15, message = "Max symbols is 15")
@Column(name = "phonenumber", length = 15, nullable = false)
private String phonenumber;
@Column(name = "surname", length = 50, nullable = false)
private String surname;
@Column(name = "firstname", length = 50, nullable = false)
private String firstname;
//getters and setter

Answer 1

我有 2 种方法来解决这个问题：--

1.( 使用 @RequestParam 获取电话簿对象，如下所示：--

@PostMapping("/save")
public String save(@Valid @RequestParam("phonenumber")String phonenumber, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
return "redirect:/";
}else {
phonebookRepository.save(p);
}
return "redirect:/";
}

OR -- 使用 @ModelAttribute 获取窗体的值，如下所示 ：--

1.( 创建一个新的电话簿对象并添加模型属性：-

@RequestMapping(value = {"/"}, method = RequestMethod.GET)
public String showPage(Model model, @RequestParam(defaultValue = "0") int page) {
//your code 
model.addAttribute("phoneBook", new Phonebook());
return "index";
}

2.( 您的百里香叶/HTML 页面中的更改(提交后使用th：object发送您的电话簿对象(：--

<form th:action="@{/save}"  method="post" th:object="${phoneBook}">
// your code
</form>

3.( 然后使用 @ModelAttribute 绑定这样的值：--

@PostMapping("/save")
public String save(@Valid @ModelAttribute("phoneBook")Phonebook p, BindingResult bindingResult) {
if (bindingResult.hasErrors()) {
return "redirect:/";
}else {
phonebookRepository.save(p);
}
return "redirect:/";
}

4.(最后是你的电话簿类与getter和setter方法。