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Azure Blob Storage

In this example I am creating, fetching and deleting files in a remote Blob Storage container. I have used dotnet secrets to set up a secret connectionstring, in DatabaseConnection.cs it is converted from secret to string. I am using the Azure.Storage.Blobs NuGet package.

Setting up Blob Storage

Here we create a new container in a specified storage account. Using this containerclient we can create, fetch and delete blobs in this container.

BlobServiceClient blobServiceClient = new BlobServiceClient("{CONNECTIONSTRING}");
string containerName = "{CONTAINERNAME}";
BlobContainerClient containerClient;
try
{
  containerClient = blobServiceClient.CreateBlobContainer(containerName);
  _containerClient = containerClient;
}
catch
{
  containerClient = blobServiceClient.GetBlobContainerClient(containerName);
  _containerClient = containerClient;
}

Creating a Blob

Firstly we reference the Blobclient object using the GetBlobClient() method. Using this we can use the UploadAsync() method to upload this file to the container.

BlobClient blobClient = _containerClient.GetBlobClient(fileName);
await blobClient.UploadAsync(localFilePath, true);

Fetching a Blob

To fetch a blob from its container, we once again reference the Blobclient object using the GetBlobClient() method. Then we modify the localFilePath to prevent duplication. Finally we us the DownloadToAsync() method to download the blob. Fetching more than one blob can be done using a forearch loop.

BlobClient blobClient = _containerClient.GetBlobClient(fileName);
string downloadFilePath = localFilePath.Replace(".txt", " DOWNLOADED.txt");
await blobClient.DownloadToAsync(downloadFilePath);
return true

Deleting a Blob

To delete a Blob we can use the DeleteBlob() method, but in this example we are deleting the entire container. This can both be achieved using the containerclient. Then we ensure that everything is cleaned up, by deleting the files we created locally.

await _containerClient.DeleteAsync();
File.Delete(localFilePath);
File.Delete(downloadFilePath);
return true;