reactjs - 上传成功后如何获取Web API返回的响应？

Question

我已经检查了文档，但没有在任何地方可以找到我需要的要求的任何详细信息。

这是一个在上传时调用的 Web API 资源，该资源返回其文件名和内容的 json。

    [HttpPost, DisableRequestSizeLimit]
    public ActionResult Upload()
    {
        try
        {
            var stamp = FileHelper.FormatShortDateForfilename(DateTime.Now, true);
            var file = Request.Form.Files[0];
            if (file.Length == 0)
                throw new Exception("No file uploaded.");

            var fileName = ContentDispositionHeaderValue.Parse(file.ContentDisposition).FileName.Trim('"');
            fileName = $"[{stamp}] {fileName}";
            var fullPath = Path.Combine(webRootPath, fileName);

            var ext = Path.GetExtension(fileName);
            if (!acceptables.Contains(ext.Replace(".", "")))
                throw new Exception($"Only {String.Join("-", acceptables).ToUpper()} files are acceptables.");

            using (var stream = new FileStream(fullPath, FileMode.Create))
            {
                file.CopyTo(stream);
            }

            dynamic upldData = new JObject();
            upldData.filename = fileName;
            upldData.Content = "........";
            return Json(upldData.ToString());
        }
        catch (Exception ex)
        {
            //return Json("Upload Failed: " + ex.Message);
            throw;
        }
    }

这是我的 ReactJS 脚本，我需要在其中访问该响应。

<FilePond ref={ref => this.pond = ref}
                server="api/imports"
                labelIdle={'Drag & Drop your CSV file here or <span class="filepond--label-action">Browse</span>'}
                checkValidity={true}
                acceptedFileTypes={['application/vnd.ms-excel']}
                onupdatefiles={fs => {
                    this.setState({ hasFile: fs.length });
                }}
                onremovefile={(fs) => {
                    this.setState({ hasFile: fs && fs.length });
                }}
                onaddfile={fs => { this.setState({ hasFile: false }) }}
                onprocessfile={(err, file) => {
                    console.log('FilePond ready for use', err, file);
                    console.log('test', file.serverId);
                }}
            />

Answer 1

我只是花了一些时间来弄清楚这里发生了什么。这是在 filePond 内创建请求的主要功能。

const createProcessorFunction = (apiUrl = '', action, name) => {
  // custom handler (should also handle file, load, error, progress and abort)
  if (typeof action === 'function') {
    return (...params) => action(name, ...params);
  }

  // no action supplied
  if (!action || !isString(action.url)) {
    return null;
  }

  // internal handler
  return (file, metadata, load, error, progress, abort) => {
    // set onload hanlder
    const ondata = action.ondata || (fd => fd);
    const onload = action.onload || (res => res);
    const onerror = action.onerror || (res => null);

    // no file received
    if (!file) return;

    // create formdata object
    var formData = new FormData();

    // add metadata under same name
    if (isObject(metadata)) {
      formData.append(name, JSON.stringify(metadata));
    }

    // Turn into an array of objects so no matter what the input, we can handle it the same way
    (file instanceof Blob ? [{ name: null, file }] : file).forEach(item => {
      formData.append(
        name,
        item.file,
        item.name === null ? item.file.name : `${item.name}${item.file.name}`
      );
    });

    // send request object
    const request = sendRequest(ondata(formData), apiUrl + action.url, action);
    request.onload = xhr => {
      load(
        createResponse(
          'load',
          xhr.status,
          onload(xhr.response),
          xhr.getAllResponseHeaders()
        )
      );
    };

    request.onerror = xhr => {
      error(
        createResponse(
          'error',
          xhr.status,
          onerror(xhr.response) || xhr.statusText,
          xhr.getAllResponseHeaders()
        )
      );
    };

    request.ontimeout = createTimeoutResponse(error);
    request.onprogress = progress;
    request.onabort = abort;

    // should return request
    return request;
  };
};

如您所见，您可以将函数或对象作为 server 属性的值传递。您可以检查一些方法，例如 onload、onerror 和 ondata 并尝试找到问题的解决方案。或者只是传递自定义函数并在其中执行您的请求，例如

<FilePond server={(...args) => this.handleUploadRequest(...args)} />

希望对你有帮助。谢谢