The download destination stream data.
This property contains a SharePointClientDownloadData object that contains the download stream information if GetDownloadStreamAsync was called to initiate the download. If DownloadFileAsync was used to initiate the download, then the value of this property will be null (Nothing in VB).
Note: You are responsible for calling System.IDisposable.Dispose on DestinationData if you subscribe to the DownloadCompleted event.
For an example, refer to GetDownloadStreamAsync.