This interface is implemented by the
HttpApplication class and defines the requirements
for asynchronous processing. It is an integral part of the ASP.NET
framework and is not used directly by ASP.NET application code.
public interface IHttpAsyncHandler : IHttpHandler {
// Public Instance Methods
public IAsyncResult BeginProcessRequest(HttpContext context, AsyncCallback cb, object extraData);
public void EndProcessRequest(IAsyncResult result);
}