Format error while trying to download excel from Azure File Share using .Net Core

Question

Hello I am trying to download the excelfiles which was uploaded through a batch to the Azure Storage Account --> File Storage.

Can you provide me a code sample to download the excel files from the Azure File Storage and send the response to the front end.

Unfortunately the below code does not work

 

public async Task<ActionResult> DownloadFileFromStorage(string url)
        {
            FileStreamResult result = null;
            try
            {
                var splittedUrl = url.Split('/');
                var fileClient = await _fileStorageService.GetShareClientAsync(splittedUrl[splittedUrl.Length - 2].ToString(), splittedUrl.Last());
                ShareFileDownloadInfo download = await fileClient.DownloadAsync();


                //var fileContent = await _fileStorageService.GetFileReferenceAsync(splittedUrl[splittedUrl.Length - 2].ToString(), splittedUrl.Last());

                byte[] fileContents = null;
                using (MemoryStream stream = new MemoryStream())
                {
                    await download.Content.CopyToAsync(stream);
                    fileContents = stream.ToArray();
                    var fileName = url.Split('/').Last();
                    return File(fileContents, "application/csv", "soxfile_2023-06-01.csv");
                }
            }
            catch (Exception ex)
            {

                throw;
            }
        }

FileStorageService.cs function

 public async Task<ShareFileClient> GetShareClientAsync(string shareName, string fileName)
        {
            var configuration = await _configurationService.GetConfigurationAsync();

            var storageCredentials = new 					StorageCredentials(configuration.Azure.StorageAccountName,
                configuration.Azure.StorageAccountKey);
            var storageAccount = new CloudStorageAccount(storageCredentials, true);
            ShareClient share = new ShareClient("DefaultEndpointsProtocol=https;AccountName=sacpquat;AccountKey=xYa/oTsWPzkNUgdTdlefU2Y5nwowmvht/cmpDPKqsMpouHggyZ5E1pCxcLUijtKQikF4DWKR+68mlycpsbpHfQ==;EndpointSuffix=core.windows.net", shareName);
            ShareDirectoryClient directory = share.GetDirectoryClient("");
            ShareFileClient file = directory.GetFileClient(fileName);
            return file;
            
        }

Answer 1

@Shetty Gunaprasad (Consultant) Thanks for posting your query on Microsoft Q&A.

Please follow the code sample provided here to download files from Azure File share in C# : https://learn.microsoft.com/en-us/dotnet/api/overview/azure/storage.files.shares-readme?view=azure-dotnet#async-apis

Regarding format error, please ensure that the extension of file being downloaded from Azure File Share matches extension of file that is saved on local disk.

Let me know the results. Thanks.

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