Question How to replace GameObject.Find or gameobject child by a for or foreach loop?

Hi,

I'd like to replace three GameObject.Find lines in Start() by a for or forreach loop but I cannot figure out how to do that.

Code (CSharp):

1.     private GameObject defaultPosition, cameraPosition2, cameraPosition3;
2.  
3.     private void Start()
4.     {
5.         // Storing the camera positions
6.         defaultPosition = GameObject.Find("DefaultPosition");
7.         cameraPosition2 = GameObject.Find("CameraPosition (2)");
8.         cameraPosition3 = GameObject.Find("CameraPosition (3)");
9.     }

These objects are children of the player; they are tagged and I use them to store different positions of the camera.

Your help would be welcome, thank you.

 

Then make your variables public and drag them in!!

Don't fight The Unity Way(tm).

(I think I posted this to you in the past...)

Remember the first rule of GameObject.Find():

Do not use GameObject.Find();

More information: https://starmanta.gitbooks.io/unitytipsredux/content/first-question.html

More information: https://forum.unity.com/threads/why-cant-i-find-the-other-objects.1360192/#post-8581066

In general, DO NOT use Find-like or GetComponent/AddComponent-like methods unless there truly is no other way, eg, dynamic runtime discovery of arbitrary objects. These mechanisms are for extremely-advanced use ONLY.

If something is built into your scene or prefab, make a script and drag the reference(s) in. That will let you experience the highest rate of The Unity Way(tm) success of accessing things in your game.

 

I could do that of course but it wouldn't tell me how to use a for loop instead.

 

You don't have to make the properties public BTW you can keep them private if you add an attribute.

Code (CSharp):

1. [SerializeField]
2. private GameObject defaultPosition

More to the point what do you want to loop over in place of using Find and why?

 

This is a poor use for a for loop because all it would do is increase the surface area for bugs by about 12x or 18x, roughly, depending on how you measure it.

Why not just look for examples of for() loops on the interwebs, rather than trying to hammer a poor idea in code (using GameObject.Find() is a BAD idea) through an inappropriate use of a simple language looping construct?

For instance you'd probabky have to containerize each GameObject variable into either its own System.Action or else into some generic class that lets you marshal it back out... it's just not appropriate.

"I have some leftover mashed potatoes from yesterday...

how can I use it to fill some of the old nail holes in my walls?"

 

What would you be for looping?

A for loop implies you have a collection to loop over. You'd have to tell us what sort of collection you'd want to loop over and why you want to do it that way?

When people mention GameObject.Find and replacing it, they're usually referring to how it's heavily suggested NOT to use GameObject.Find and would like a cleaner alternative.

Well... that cleaner alternative is exactly what @Kurt-Dekker suggested.

I mean if you REALLY want to use some loop. Well your conditions have various "collections" you could easily form:
1) since they're children you can enumerate all the children (could use something like GetComponentsInChildren<Transform>(), or just enumerate the Transforms, etc)
2) since they're tagged you could enumerate the FindObjectsWithTag collection
3) you could attach a script to them that has a static collection that puts them in the collection on awake/onenable/start or whatever (timing becomes an issue here)

But I mean... why? Why do it that way?

Is this like a question on a test/homework/exam? If so... either there is more to the question that explains context, or it's just a really bad question on a test.

 

https://docs.unity3d.com/ScriptReference/GameObject.Find.html

 

It sounds like the dots aren't quite being connected here... You accessed the methods in Start not Update as the example points out. The questions were "why a loop" and "loop over what"?

 

As was already said, you cannot utilize a for/foreach loop here, because you need to assign values to distinct fields (

defaultPosition

,

cameraPosition2

...), not to indexes in a collection (

cameraPositions[0]

,

cameraPositions[1]

...).

Well, in theory you could, if you were to define a custom indexer in the class to map from an index to a field using a switch expression - but I don't think that would make any sense for your use case...

Code (CSharp):

1. GameObject this[int index]
2. {
3.     set
4.     {
5.         switch(index)
6.         {
7.             case 0: defaultPosition = value; break;
8.             case 1: cameraPosition2 = value; break;
9.             case 2: cameraPosition3 = value; break;
10.         }
11.     }
12. }
13.  
14. void Start()
15. {
16.     var names = new[] { "DefaultPosition", "CameraPosition (2)", "CameraPosition (3)" };
17.     for(int i = 0; i < 3; i++)
18.     {
19.         this[i] = GameObject.Find(names[i]);
20.     }
21. }

One thing you could do is use a tuple's deconstructor to assign to multiple fields in one go:

Code (CSharp):

1. void Start() => (defaultPosition, cameraPosition2, cameraPosition3)
2.              = (Find("DefaultPosition"), Find("CameraPosition (2)"), Find("CameraPosition (3)"));

But I don't think that would be more readable either than just three separate assignment operations

 

Your repeated lack of context for your statements is very confusing.

What does this have to do with a for loop?