wait fault

waituntilfault.cs

public static void WaitUnlessFault( Task[] tasks, CancellationToken token )
{
    var cts = CancellationTokenSource.CreateLinkedTokenSource(token);

    foreach ( var task in tasks ) {
        task.ContinueWith(t =>
        {
            if ( t.IsFaulted ) cts.Cancel();
        },
        cts.Token,
        TaskContinuationOptions.ExecuteSynchronously,
        TaskScheduler.Current);
    }

    try {
        Task.WaitAll(tasks, cts.Token);
    }
    catch ( OperationCanceledException ex ) {
        var faultedTaskEx = tasks.Where(t => t.IsFaulted)
            .Select(t => t.Exception)
            .FirstOrDefault();

        if ( faultedTaskEx != null )
            throw faultedTaskEx;
        else
            throw;
    }
}