Invoking Action with no subscribers | Official Unity Discord | Page 1

lucid fractal Mar 19, 2026, 9:47 PM

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I'm trying to use an OnHit action that I made by doing OnHit.Invoke() but when it has no subscribers, it gives NullReferenceError. I then tried to do the following but I still get NullReferenceError on the conditional.

if(OnHit.GetInvocationList().Length > 0)
    OnHit.Invoke();

latent plank Mar 19, 2026, 9:48 PM

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A delegate/event that has no subscribers should be null. You can safely invoke it by doing OnHit?.Invoke()

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The null ref exception you got should have made that clear

lucid fractal Mar 19, 2026, 9:49 PM

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Thanks

latent plank Mar 19, 2026, 9:49 PM

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Related note, I recommend use of the event keyword:
public event Action OnHit;

lucid fractal Mar 19, 2026, 9:49 PM

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latent plank The null ref exception you got should have made that clear

I thought it was somehow trying to invoke the first element of an empty list. Didn't think it would be null itself

lucid fractal Mar 19, 2026, 9:50 PM

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Yes, that's what I'm doing

latent plank Mar 19, 2026, 9:50 PM

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Great 👍

lucid fractal Mar 19, 2026, 9:51 PM

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Thanks for the help

remote cairn Mar 20, 2026, 2:59 PM

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btw, you may have heard that ?. isn't safe to use in Unity

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this is specifically for unity objects -- anything inheriting from UnityEngine.Object

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it's "unsafe" because it only checks if the object is actually a null reference

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unity objects have overloaded the == operator so that obj == null is true when obj is a destroyed unity object

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?. will not check for this, so obj?.transform will throw an error if obj is destroyed

lucid fractal Mar 20, 2026, 11:45 PM

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But that is not relevant in the case of actions, right?

#Invoking Action with no subscribers