namespace System.Runtime { internal abstract class AsyncResult : IAsyncResult { protected delegate bool AsyncCompletion (IAsyncResult result); public object AsyncState { get; } public WaitHandle AsyncWaitHandle { get; } public bool CompletedSynchronously { get; } public bool HasCallback { get; } public bool IsCompleted { get; } protected Action<AsyncResult, Exception> OnCompleting { get; set; } protected Action<AsyncCallback, IAsyncResult> VirtualCallback { get; set; } protected AsyncResult(AsyncCallback callback, object state); protected void Complete(bool completedSynchronously); protected void Complete(bool completedSynchronously, Exception exception); protected virtual bool OnContinueAsyncCompletion(IAsyncResult result); protected void SetBeforePrepareAsyncCompletionAction(Action beforePrepareAsyncCompletionAction); protected void SetCheckSyncValidationFunc(Func<IAsyncResult, bool> checkSyncValidationFunc); protected AsyncCallback PrepareAsyncCompletion(AsyncCompletion callback); protected bool CheckSyncContinue(IAsyncResult result); protected bool SyncContinue(IAsyncResult result); protected static void ThrowInvalidAsyncResult(IAsyncResult result); protected static void ThrowInvalidAsyncResult(string debugText); protected static TAsyncResult End<TAsyncResult>(IAsyncResult result) where TAsyncResult : AsyncResult; } }