Question

I have used the web client method to download images using a background worker in my wp7 app. I came to know the webclient method usually run in the UI thread by default. So now there is a confusion that wheather the webclient run in the backround thread or UI thread in the app even if it is mention inside the background worker class

Answer 1

The execution of a WebClient request will run on the thread it is called on, unless it has a Async suffix at the end of it’s method name. (For example DownloadData(Uri) will run on the same thread as the call. DownloadDataAsync(Uri) will run on a new background thread)

If you’re using a BackgroundWorker to call your WebClient requests it will not be executed on the UI thread (Both using the Download and DownloadAsync methods), because BackgroundWorker already runs it’s code in a background thread in the first place.

EDIT: Looking at your tags, it should be noted that Silverlight (and thereby Windows Phone 7) only supports the Async versions of the WebClient calls.