Question

I’m porting Android application that uses REST API to WP7 platform.

In Android all of REST API calls are blocking and I manually use Executors to balance threads doing network I/O.

In WP7 and Silverlight I have to use HttpWebRequest.BeginGetResponse and it has only async variant of reading response.

Is it:

1) Uses something like I/O Asynchronous Completion and it’s really async?
or
2) Just uses blocking read / write operations inside + thread behind it?

Answer 1

I just checked the source code using Reflector, it’s a blocking call executed on the thread pool.

public override IAsyncResult BeginGetResponse(AsyncCallback callback, object state)
{
    this.startGetResponse();
    LazyAsyncResult result = new LazyAsyncResult(this, state, callback);
    if (!ThreadPool.QueueUserWorkItem(new WaitCallback(this.asyncGetResponse), result, true))
    {
        throw new OutOfMemoryException(SR.GetString(0x49, new object[0]));
    }
    return result;
}