Question

我正在开发Spring + Thymeleaf应用程序。我正在用多个参数实现搜索。我有一个表格与相应的DTO。以下是DTO的代码：

public class ClassSearchDto {
   private String searchParam;
   private Long programId;
   private List<String> teacherNames;
   //getters, setters and constructor are omitted
}

如您所见，我的DTO中有一个名为teacherNames的字符串列表。这是我显示表单的方式：

 <form th:action="@{/classes/search}" method="get" th:object="${classSearchDto}">

    <div class="form-group">
       <input type="hidden" class="form-control"
          th:value="${classSearchDto.programId}" th:field="*{programId}"/>

       <label for="searchParam">Search</label>
       <input type="text" class="form-control" id="searchParam" placeholder="keyword"
                                       th:value="${classSearchDto.searchParam}" th:field="*{searchParam}"/>
       <div>
          <th:block th:each="name, iter ${classSearchDto.teacherNames}">
              <input th:value="${name}" th:field="*{teacherNames[__${iter.index}__]}/>
          </th:block>
       </div>

   </div>
   <button class="btn btn-default" type="submit">Find</button>

   </form>

我想在后端使用@RequestParam注释帮助实现我的搜索。这是我的控制者：

 @RequestMapping(value = "/search")
 public String findClassByName(@RequestParam("searchParam") final String searchParam,
                              @RequestParam("programId") final Long programId,
                              @RequestParam("teacherNames") final List<String> teacherNames,
                              final Model model) {
 ...
 }

问题在于我无法以这种方式获得教师姓名列表。我得到了这个例外：

 org.springframework.web.bind.MissingServletRequestParameterException:Required List parameter 'teacherNames' is not present

请您帮我用这种方法将DTO中的元素列表转移到我的后端？也许你知道如何以另一种方式正确地做到这一点。提前谢谢。

Answer 1

我可以建议你一件事，我不知道它是否有效。尝试更改

public String findClassByName(@RequestParam("searchParam") final String searchParam,@RequestParam("programId") final Long programId,@RequestParam("teacherNames") final List<String> teacherNames,final Model model)

到

public String findClassByName(@ModelAttribute("classSearchDto")  ClassSearchDto classSearchDto,@RequestParam("searchParam") String searchParam,@RequestParam("programId") Long programId,@RequestParam("teacherNames")  List<String> teacherNames,Model model)

如何使用Thymeleaf传输DTO中的字符串列表

1 个答案: