You have local disk access, where you can construct your new file exactly how you're doing it now. Once you finish constructing the file, you can just copy the file to a blob (which is supported via the blob REST API, and wrapped by the .NET SDK and other language SDKs). Just look at the CloudBlockBlob
class and the methods UploadFromFile
and UploadFromFileAsync
(there are also methods to upload from stream).
There's also a CloudBlobStream
class that supports reading and writing.