Question

I’m invoking a REST service via http which returns a stream as the response.
My client code looks like so:

                Uri uri = new Uri(remoteAddress);
                var webRequest = (HttpWebRequest)WebRequest.Create(uri);
                webRequest.Method = "GET";
                webRequest.ContentType = "multipart/mixed";
                webRequest.BeginGetResponse(responseResult =>
                {
                    HttpWebResponse response = (HttpWebResponse)webRequest.EndGetResponse(responseResult);
                    this.messages = ParseResponse(response);
                    Complete(false);
                }, null);

I’m getting the following error on this line:

 HttpWebResponse response = (HttpWebResponse)webRequest.EndGetResponse(responseResult);

System.Net.ProtocolViolationException was unhandled by user code
Message=Operation is not valid due to the current state of the object.
StackTrace:
at System.Net.Browser.AsyncHelper.BeginOnUI(SendOrPostCallback beginMethod, Object state)
at System.Net.Browser.BrowserHttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at LaharSubProxy.SubscribeAsyncResult`1.<>c__DisplayClass1.b__0(IAsyncResult responseResult)
at System.Net.Browser.BrowserHttpWebRequest.<>c__DisplayClassd.b__b(Object state2)
at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
at System.Threading.ThreadPoolWorkQueue.Dispatch()
at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()
InnerException:

This is driving me absolutely nuts since the exception is not pointing to anything useful. I have enabled the “streaming” option in fiddler but I’m not seeing any traffic/errors.

Please help!

Answer 1

Well whatdya know, the problem is this line:

webRequest.ContentType = "multipart/mixed";

Seems like this is a SL bug/nuance. I commented that line out and the error disappears!
I should also add that the code as is works just fine in a traditional console/windows app.

This post pointed me the right direction. Thanks Microsoft!!!!!!