Welcome to the Lounge

Quote:

Pandora's given a box by a God, told not to open it - she does and unleashes pain into the world

Task WaitForThatEventAsync(Foo source)
{
    var res = new TaskCompletionSource<bool>();
    EventHandler eh = null;
    eh = (o, e) =>
    {
        source.ThatEvent -= eh;
        res.TrySetResult(true);
    };
    source.ThatEvent += eh;
    return res.Task;
}

EventHandler ev = null;
ev = (o, e) => {
  source.Event -= eh;
  DoSomething();
};
source.Event += eh;

await source.Event.WaitForEvent()
DoSomething();