Creating Zip Files from Memory Stream C#

Question

Basically the user should be able to click on one link and download multiple pdf files. But the Catch is I cannot create files on server or anywhere. Everything has to be in mem

Answer 1

Below code is to get files from a directory in azure blob storage, merge in a zip and save it in azure blob storage again.

    var outputStream = new MemoryStream();
    var archive = new ZipArchive(outputStream, ZipArchiveMode.Create, true);

    CloudBlobDirectory blobDirectory = appDataContainer.GetDirectoryReference(directory);
    
    var blobs = blobDirectory.ListBlobs();

    foreach (CloudBlockBlob blob in blobs)
    {
        var fileArchive = archive.CreateEntry(Path.GetFileName(blob.Name),CompressionLevel.Optimal);

        MemoryStream blobStream = new MemoryStream();
        if (blob.Exists())
        {
            blob.DownloadToStream(blobStream);
            blobStream.Position = 0;
        }

        var open = fileArchive.Open();
        blobStream.CopyTo(open);
        blobStream.Flush();
        open.Flush();
        open.Close();

        if (deleteBlobAfterUse)
        {
            blob.DeleteIfExists();
        }
    }
    archive.Dispose();

    CloudBlockBlob zipBlob = appDataContainer.GetBlockBlobReference(zipFile);

    zipBlob.UploadFromStream(outputStream);

Need the namespaces:

• System.IO.Compression;
• System.IO.Compression.ZipArchive;
• Microsoft.Azure.Storage;
• Microsoft.Azure.Storage.Blob;