Await extension method for Task

TaskExtensions.cs

public static class TaskExtensions
{
    public async static void Await(this Task task, Action onCompleted, Action<Exception> onError)
    {
        try
        {
            await task;
            onCompleted?.Invoke();
        }
        catch (Exception ex)
        {
            onError?.Invoke(ex);
        }
    }
}