Gets downloaded data from a successful download request.
You generally use this property only from within the event handler for a Downloader Completed event. Outside this context, there is no guarantee that a ResponseText value is valid.
If you are requesting parts of a package, use GetResponseText.
If you are downloading media assets for use by the Source property of Image and MediaElement objects, you should consider using the SetSource (Image) or SetSource (MediaElement) methods instead of setting an object with GetResponseText or ResponseText, and then setting the Source properties. This is a more efficient way to transfer large-sized media assets. Image also has an equivalent SetSource.