facilitates async await

StaticAsyncMediator.cs

    public static class StaticAsyncMediator
    {
        private static readonly IDictionary<string, object>
            CompletionSources = new ConcurrentDictionary<string, object>();

        private static TaskCompletionSource<T> GetCreateSource<T>(string key)
        {
            var fullKey = $"{typeof(T).FullName}:{key}";
            if (CompletionSources.ContainsKey(fullKey) && CompletionSources.TryGetValue(fullKey, out var returnValue))
                return (TaskCompletionSource<T>) returnValue;

            var newTaskCompletion = new TaskCompletionSource<T>(TaskCreationOptions.LongRunning);
            CompletionSources.TryAdd(fullKey, newTaskCompletion);
            return newTaskCompletion;
        }

        public static void RegisterResult<T>(T result, string key = "")
        {
            var source = GetCreateSource<T>(key);
            source.SetResult(result);
        }

        public static async Task<T> GetResultAsync<T>(string key = "")
        {
            var source = GetCreateSource<T>(key);
            return await source.Task;
        }
    }