java - com.fasterxml.jackson.databind.exc.InvalidDefinitionException : Cannot construct instance of `org.springframework.web.multipart.MultipartFile`

Question

我正在尝试从 spring boot Controller 访问上传的文件，但出现错误

com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of springframework.web.multipart.MultipartFile

表单域类

public class FormDomain {
     @JsonPropertyDescription
 private MultipartFile fileInput;

public MultipartFile getFileInput() {
    return fileInput;
}

public void setFileInput(MultipartFile fileInput) {
    this.fileInput = fileInput;
}

}

表单 Controller 类

@CrossOrigin(origins="*")
@RestController
public class FormController {
      @PostMapping(path="/basicForm")
 public String postResponseController(
              @RequestBody FormDomain loginForm) throws IOException {
         return "file transfer completed successfully";
     }

Angular 形式

<form #basicForm = "ngForm" (ngSubmit) = "onClickSubmit(basicForm.value)" enctype="multipart/form-data" class="form-horizontal">
    <input type="file" id="file-input" name="fileInput" ngModel (change)="selectFile($event)">
     <button type="submit"> Submit</button>
 </form>

选择文件方法

 selectFile(event) {
    this.selectedFiles = event.target.files[0];
    console.log(this.selectedFiles);
    }

提交表单的 Angular 方法

   onClickSubmit(data) {
             data.fileInput=this.selectedFiles;
        this.http.post("http://localhost:8080/basicForm", data).subscribe( (ob)=>(console.log("subscribe method called")));

  }

如何解决这个问题？

Answer 1

RequestBody 注解是不可能的。

您可以通过如下方式实现。

public String postResponseController(@RequestParam("multipartFile") MultipartFile multipartFile) throws IOException {
//do somthing
}

希望对您有所帮助。