Question

I use WebRequest.BeginGetResponse in order to retrieve a resource asynchronously.

Is it possible using this async way to be notified if a timeout occurred for the specified resource ?

HttpWebRequest request = (HttpWebRequest) WebRequest.Create(url);
var asyncResult = req.BeginGetResponse(new AsyncCallback(RespCallback), req);

Answer 1

HttpWebRequest has a Timeout property.

Using BeginGetResponse on timeout the returned IAsyncResult will be signalled as completed or the callback passed to BeginGetResponse will be called. When you then call EndGetResponse the exception indicating the timeout will be thrown.