private static object EndSyncImpl(IAsyncResult asyncResult)
{
if (asyncResult == null)
{
throw new ArgumentNullException("asyncResult");
}
SynchronousAsyncResult syncResult = asyncResult as SynchronousAsyncResult;
if (syncResult == null)
{
throw new ArgumentException("IAsyncResult object did not come from the corresponding async method on this type.", "asyncResult");
}
//
// IMPORTANT! The End method on SynchronousAsyncResult will
// throw an exception if that's what Log did when
// BeginLog called it. The unforunate side effect of this is
// the stack trace information for the exception is lost and
// reset to this point. There seems to be a basic failure in the
// framework to accommodate for this case more generally. One
// could handle this through a custom exception that wraps the
// original exception, but this assumes that an invocation will
// only throw an exception of that custom type.
//
return(syncResult.End());
}
//
// The following two methods are helpers that provide boilerplate
// implementations for implementing asnychronous BeginXXXX and
// EndXXXX methods over a default synchronous implementation.
//
private static IAsyncResult BeginSyncImpl(AsyncCallback asyncCallback, object asyncState, Delegate syncImpl, params object[] args)
{
Debug.Assert(syncImpl != null);
SynchronousAsyncResult asyncResult;
var syncMethodName = syncImpl.Method.Name;
try
{
asyncResult = SynchronousAsyncResult.OnSuccess(syncMethodName, asyncState,
syncImpl.DynamicInvoke(args));
}
catch (Exception e)
{
asyncResult = SynchronousAsyncResult.OnFailure(syncMethodName, asyncState, e);
}
if (asyncCallback != null)
{
asyncCallback(asyncResult);
}
return(asyncResult);
}