title: Async call to WCF with C#?
body: <p>In C#, how do I make an async call to a WCF Web Service? I have a Service Reference set up to generate async. I also modified my calls to use { WebServiceObject.Begin* () } but there are two parameters at the end, 'AsyncCallback' and 'object asyncState'. What are these and how do I use them?</p>
  
  <p>Thanks,</p>