c# - MS 上传大文件 - 无效请求错误消息。怀疑切片大小

public async Task<Boolean> UploadPhysicalFileToSharepoint(string filePath, string filename) { using (var fileStream = System.IO.File.OpenRead(filePath)) { // Use properties to specify the conflict behavior // in this case, replace var uploadProps = new DriveItemUploadableProperties { ODataType = null, AdditionalData = new Dictionary<string, object> { { "@microsoft.graph.conflictBehavior", "replace" } } }; // Create the upload session //https://docs.microsoft.com/en-us/graph/api/driveitem-createuploadsession?view=graph-rest-1.0 var uploadSession = await _graphServiceClient .Drives[largeBlobsDocumentLibraryID] .Root .ItemWithPath(filename) .CreateUploadSession(uploadProps) .Request() .PostAsync(); // how big should this be???? int maxSliceSize = 320 * 2048 * 1024 var fileUploadTask = new LargeFileUploadTask<DriveItem>(uploadSession, fileStream, maxSliceSize); // Create a callback that is invoked after each slice is uploaded IProgress<long> progress = new Progress<long>(prog => { Console.WriteLine($"Uploaded {prog} bytes of {fileStream.Length} bytes"); }); try { // Upload the file var uploadResult = await fileUploadTask.UploadAsync(progress); if (uploadResult.UploadSucceeded) { // The ItemResponse object in the result represents the // created item. Console.WriteLine($"Upload complete, item ID: {uploadResult.ItemResponse.Id}"); return true; } else { Console.WriteLine("Upload failed"); return false; } } catch (ServiceException ex) { var retry = await fileUploadTask.ResumeAsync(progress); Console.WriteLine($"Error uploading: {ex.ToString()}"); return false; } }