// technically we can even subscribe to delegate-typed members without events
// at all but it is more limited
// return true if success, false if failure
public bool Play()
{
Console.WriteLine("Playing Movie.");
// wait for 3 seconds
Thread.Sleep(3000);
// firing the MovieFinished event
// null-check because if there are zero subscribers,
// that is a null reference exception
//if (MovieFinished != null)
//{
// MovieFinished();
//}
MovieFinished?.Invoke();
// this will call not just one function, but all event subscribers.
// ?. is a special operator called the null-coalescing operator
// If the thing to the left is null, it simply returns null.
// if the thing to the left is NOT null, it will behave like . (dot)
// ?? is the null-coalescing operator
// a ?? b, that means, return a, unless it's null, in which case return b.
// When we fire the event, we provide all parrameters that the event
// says its handlers needs
DiscEjected?.Invoke(CurrentMovie.ToString());
return(true);
}
//technically we can even subscribe to delegate-typed members
// without events at all, but it's a bit more limited
//return true if success, false if failure
public bool Play()
{
//wait for 3 seconds
Thread.Sleep(3000);
//firing the MovieFinished event
//must null-check because if there are zero subscribers,
// that's a nullreferenceexception
//if (MovieFinished != null)
//{
// if (MovieFinished != null)
// MovieFinished();
//}
MovieFinished?.Invoke();
//this will call not just one function but all event subscribers
//?. is a special operator called the null-coalescing operator
//if the thing to the left of it is null, it simply returns null
//if the thing to the left is NOT null, it will behave like .(dot)
//?? is the null-coalescing operator
//a ?? b, means return a unless it's null, in which case return b
//when we fire the event, we provide all parameters that the event
// says its handlers need
DiscEjected?.Invoke(CurrentMovie.ToString());
return(false);
}
// technically we can even subscribe to delegate typed members without events at all
// but it's a bit more limited
// return true if success, false if failure
public bool Play()
{
// wait 3 secs
Thread.Sleep(3000);
// firing the Moviefinished event
// must null check because there are 0 subscribers
// nullReferenceException
//if (MovieFinished is null)
//{
// MovieFinished();
//}
// firing the MovieFinished Event
MovieFinished?.Invoke();
// will not just call one fn, but all event subscribers
// `?.` is a special operator called the null coalescing operator
// if the thing to left is null, it returns null
// if thing to the left is not null, will behave like .
// `??` is the null coalescing operator
// a ?? b, means return a, unless it's null, in which case returns b
// when we fire the event, we provide all the params that the event says it needs
DiscEjected?.Invoke(CurrentMovie.ToString());
return(true);
}
public void PlayMovie()
{
Console.WriteLine($"Play movie {CurrentMovie}");
Thread.Sleep(3000);
//Fire event
MovieFinished?.Invoke();
}
// will return true if success, false if not
public bool Play()
{
Thread.Sleep(3000);
MovieFinished?.Invoke();
return(false);
}
public void PlayMovie()
{
Console.WriteLine($"Playing movie {CurrentMovie}");
Thread.Sleep(3000);
//if (MovieFinished != null)
//{
// MovieFinished();
//}
MovieFinished?.Invoke();
}
public void PlayMovie()
{
Console.WriteLine($"Playing movie {CurrentMovie}");
Thread.Sleep(3000);
//fire the event (syntax looks just like calling a method)
//what it effectively does is call all subscribing delegates
//weird issue - if there are no subscribers, the event is kind of "null"
/*if(MovieFinished != null)
* MovieFinished(CurrentMovie);*/
MovieFinished?.Invoke(CurrentMovie); //does same thing as above code - do nothing if no subscribers
//when you invoke the event, you have to pass the name of the event
}
public void PlayMovie()
{
Console.WriteLine($"Playing movie {CurrentMovie}");
Thread.Sleep(3000); // wait for 3 seconds
// fire the event. (the syntax looks just like calling a method)
// what it effectively does is call all the subscribing delegates
// weird issue - if there are no subscribers, the event is kind of "null"
//if (MovieFinished != null)
//{
// MovieFinished(CurrentMovie);
//}
MovieFinished?.Invoke(CurrentMovie); // does same thing as above code - do nothing if no subscribers
// when you invoke the event, you have ot pass it the parameters the handlers want
}
// technically we can subscribe to delegate-typed members without events at all
// but it's a bit more limited
//return true if success, false if failure
public bool Play()
{
//wait for 3 seconds
Thread.Sleep(3000);
// Firing the MovieFinished event
// MovieFinished();
// this will call not just one function, but all event subscribers.
MovieFinished?.Invoke();
// ?. is a special operator called the null-coalescing operator
// if the thing to the left of it is null, it simply returns null.
// if the thing to the left is not null, it will behave like .
// when we fire the event, we provide all parameters that the event
// needs
DiscEjected?.Invoke(CurrentMovie.ToString());
return(true);
}
public void PlayMovie()
{
Console.WriteLine($"Playering {CurrentMovie}");
//Mmovie plays... placeholder code here
Thread.Sleep(3000); //wait for 3 seconds
//fire the event. (the syntax looks just like calling a method)
//what is effectively does is call all the subscribing delegates
//if there are no subscribers, the event is null.
//if (MovieFinished != null)
//{
// MovieFinished();
//}
//better way
MovieFinished?.Invoke(); // better, modern: do nothing if no subscribers...
}
public bool Play()
{
Thread.Sleep(3000);
// fire event
//if (MovieFinished != null)
//{
// MovieFinished();
//}
// ?. is a special operator called the null-coalescing operator
// if the thing to the left of it is null, it simply returns null.
// if the thing to the left is not null, it will behave like .
// ?? is the null-coalescing operator
// a ?? b, that means, return a, unless it's null, in which case return b.
MovieFinished?.Invoke();
// this calls all event subscribers
DiscEjected?.Invoke(CurrentMovie.ToString());
return(true);
}
