我正在处理来自 React 客户端的 aws s3 照片上传，但遇到以下错误：

TypeError: Cannot read property 'byteLength' of undefined

我假设上传对象存在缺陷，但我相信 s3/cognito 配置可能有问题，因为我在调用s3.listObjects. 我正在关注这些文档 - https://docs.aws.amazon.com/sdk-for-javascript/v2/developer-guide/s3-example-photo-album-full.html

有什么想法吗？

uploadPhoto() {
        const files = document.getElementById("photoUpload").files;
        if (!files.length) {
          return alert("Please choose a file to upload first.");
        }
        const file = files[0];
        const fileName = file.name;
        const albumPhotosKey = encodeURIComponent('screenshots') + "/";
      
        const photoKey = albumPhotosKey + fileName;
        
        // Use S3 ManagedUpload class as it supports multipart uploads
        
        const upload = new AWS.S3.ManagedUpload({
            params: {
              Bucket: <Bucket Name>,
              Key: fileName,
              Body: file
            }
          });

        const promise = upload.promise();
      
        promise.then(
          function(data) {
            alert("Successfully uploaded photo.");
            console.log('UPLOAD: ', data)
          },
          function(err) {
              console.log('ERROR: ', err)
            // return alert("There was an error uploading your photo: ", err.message);
          }
        );
      }