Get Array BoxCollider2D

Hi.

In my scene i have many box objects that they contain many box child and i want get all box child colliders in Start() function like below, but it only can get box child colliders in one box objects. how can get all of them?

Code (CSharp):

1.  
2. private BoxCollider2D[] BoxCollider;
3.  
4.     void Start ()
5.     {
6.       BoxCollider = GameObject.FindGameObjectWithTag("BoxObject").GetComponentsInChildren<BoxCollider2D>();
7.     }
8.  

 

If you just want to grab all the box colliders at start, the simplest call is just FindObjectsOfType<BoxCollider2D>().

The code you have above finds a single game object by name (the first one called "BoxObject"), then gets the BoxCollider2Ds on that one game object, which is why you only get the one.

As an aside, don't run that code every frame. It will kill your performance. At scene startup is fine obviously, as it won't be noticed.

 

He beat me to it, but another option (if possible) is to add [SerializeField] on your array and simply drag every single one in from the inspector lol

If getting every type doesn't work, use the plural for tags. Still better to use the inspector, imo, but nevertheless, there is the method: https://docs.unity3d.com/ScriptReference/GameObject.FindGameObjectsWithTag.html

Using that you can collect all of the box colliders. Probably best with a list, that you can then convert to an array for your variable.

 

Thanks for reply.

In my scene there are many BoxCollider2D and i need get only BoxCollider2D for BoxObject. because i want disable and enable isTrigger for them.

 

Thanks @methos5k

seem i don't have better choice and should be add them in inspector.

 

The inspector is by far the best, if it's available (I mean if they're in the scene).

You're welcome.

 

i forget one thing that for each BoxObject, should i add new BoxCollider2D[] variable?

 

Do you want 1 array of child box colliders for each BoxObject?

Or 1 array with every box collider of box object and children?

 

yes. but it seem impossible. right?

EDIT: i want when i collide to each BoxObject, all child box collider save to BoxCollider2D[].
i do this with OnCollisionEnter2D(), but this way make exist some problem.

 

Nope. If you want one per BoxObject (1 array for itself + all children), I would say you should try this:

Code (csharp):

1. BoxCollider2D [] boxes;
2. void Start() {
3.    boxes = GetComponentsInChildren<BoxCollider2D>();
4.  }
5.  

Edited this portion: That includes all children and children of children, etc..
(before the edit, I thought maybe it was only 1 deep. should have checked first )

 

According to your edit, I'm not sure there's any difference. Unless the children are modified at runtime, then it's the same if you store them early or on collision. By 'same', I mean you'll get same list. It's better to store them once (either from the inspector), or getting all child components in Start(), though. That's compared to fetching them anew on collision.

 

Thanks @methos5k for your guides.

 

No problem