public override Stream CreateUploadStream(IStorageProviderSession session, ICloudFileSystemEntry fileSystemEntry, long uploadSize)
{
// build the url
string url = GetResourceUrl(session, fileSystemEntry, null);
// get the session creds
ICredentials creds = session.SessionToken as ICredentials;
// build the webrequest
FtpWebRequest networkRequest = (FtpWebRequest)_ftpService.CreateWebRequest(url, WebRequestMethodsEx.Ftp.UploadFile, creds, false, null);
// set the binary mode
networkRequest.UseBinary = true;
// Notify FTP of the expected size
networkRequest.ContentLength = uploadSize;
// get the request stream
WebRequestStream requestStream = _ftpService.GetRequestStream(networkRequest, uploadSize);
// add disposal opp
requestStream.PushPostDisposeOperation(CommitUploadStream, _ftpService, networkRequest, fileSystemEntry, requestStream);
// go ahead
return(requestStream);
}