Destroy all Children!

Haha the title.

I want to destroy all children of a game object with the following while. I think every loop should destroy one Child until there are none left and the condition is met but it loops infinitely and crashes.

Code (CSharp):

1.  while( eP.transform.childCount != 0)
2.         {
3.             Destroy(eP.transform.GetChild(0));
4.         }

Can somebody tell me why please?

 

Read the manual:

https://docs.unity3d.com/ScriptReference/Object.Destroy.html

So just go through the list of children and destroy them. Better if you put them in a parent game object and just destroy that one (in case you need eP in the future).

 

You're trying to destory the trasnform, you need to destroy the game object.

Code (CSharp):

1.   Destroy(eP.transform.GetChild(0).gameObject);

 

You could also do the following foreach:

Code (CSharp):

1. foreach(Transform child in eP.transform)
2. {
3.     Destroy(child.gameObject);
4. }

If you want to keep it the same way as you have, the answer from the person above is most likely what you are looking for.

 

If you destroy a GameObject will it's components be automatically garbage collected by the Unity Engine?

 

Yes.

 

That looks so clean and easy, and as many clean and easy solutions:
it doesnt work!
Result: it kills only half the children.

I think it translates into something like (EXAMPLE)

child[0] Anna
child[1] Bob
child[2] Caspar

kill them all -> kill child[0] then kill child[1] then kill child[2]

1) kill child[0] -> Anna dies (now Bob is child[0] and Caspar is child[1] )
2) kill child[1] -> Caspar dies (now only bob is left as Child[0] )
3) kill child[2] -> no child[2]
Hey, who are you?
I am Bob.
Are you child[2]
no i am child [0]
okay go!

I dont trust while but:

while ( transform.childCount>0) Destroy(transform.GetChild(0).gameObject);

 

And that's why you always move backwars in a for loop when you execute code that can alter the collection. Actually it's fascinating that you don't got a CollectionModified exception.

Code:

Code (CSharp):

1. for(int i = eP.transform.childCount - 1; i >= 0; i--)
2. {
3.     Destroy(eP.transform.GetChild(i).gameObject);
4. }

 

I mean using Destroy means they don't actually get destroyed until the end of the frame. It's more akin to flagging something for destruction.

I've used the code that 'doesn't work' plenty of times with zero issues.

 

How are you using the code, where is this loop called from?
Like @spiney199 said, this code should work just fine.

 

you need to use a coroutine ı preffer IEnumerator and make the frames wait for one tick which you can do it by

Code (CSharp):

1. private IEnumerator destoryAllChildren(){
2.     while ( transform.childCount>0) {
3.         Destroy(transform.GetChild(0).gameObject);
4.         yield return null;
5.     }
6. }

writing using System.Collections; at the begginning of the whole code is a need
and to call the function we use StartCoroutine e.g.;

Code (CSharp):

1. StartCoroutine(destoryAllChildren(///overload\\\));

 

You don't need to use a coroutine. The following code adds two extensions that can delete children of a gameobject, in one frame. You need to use the second one in editor scripts.
After you add the code, you can use it as follows:

Code (CSharp):

1. var gameObject = Find("SomeGameObject");
2. gameObject.DestroyChildren();

Code (CSharp):

1.  
2. public static class GameObjectExtensions {
3.   public static void DestroyChildren(this GameObject t) {
4.       t.transform.Cast<Transform>().ToList().ForEach(c => Object.Destroy(c.gameObject));
5.   }
6.  
7.   public static void DestroyChildrenImmediate(this GameObject t) {
8.       t.transform.Cast<Transform>().ToList().ForEach(c => Object.DestroyImmediate(c.gameObject));
9.   }
10. }
11.  

 

That is an absurdly unnecessary amount of Linq that could be done with just:

Code (CSharp):

1. public static void DestroyAllChildren(this GameObject go)
2. {
3.     foreach (Transform transform in go)
4.     {
5.         UnityEngine.Object.Destroy(transform.gameObject);
6.     }
7. }