Alternative to unityeditor.ArrayList.Remove() for array variable type?

Hello!
I was making a script to remove the objects in my array once they were destroyed, I stumbled across ArrayList.Remove() and it was perfect, until I realized that it only works inside the unity editor, so I tried making a workaround and eventually got to this

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEditor;
5. using UnityEngine.SceneManagement;
6. public class GameManager : MonoBehaviour
7. {
8.     public GameObject[] enemies;
9.     private float nullCount = 0;
10.     // Start is called before the first frame update
11.     void Start()
12.     {
13.        
14.     }
15.  
16.     // Update is called once per frame
17.     void Update()
18.     {
19.         foreach(GameObject currentEnemy in enemies)
20.         {
21.             if (currentEnemy)
22.             {
23.                 Debug.Log("Enemy Still Alive!");
24.                 nullCount -= 1;
25.                 nullCheck();
26.             }
27.             else if (!currentEnemy)
28.             {
29.                 Debug.Log("Enemy Dead");
30.                 nullCount += 1;
31.                 enemies[System.Array.IndexOf(enemies, currentEnemy)] = null;
32.                 nullCheck();
33.             }
34.         }
35.        
36.     }
37.  
38.     void nullCheck()
39.     {
40.         if (nullCount == 0)
41.         {
42.             SceneManager.LoadScene("Scene 3");
43.         }
44.     }
45. }
46.  

The problem with this system is that if my player is say a speed runner and he brutally murders every enemy within 0.69 seconds this will cause the game to take forever to move on to the next scene.

I want to know a faster way of doing this, or even better, an alternative to ArrayList.Remove.

(Also sorry for no comments, I only use them on huge scripts.)

 

Arrays are immutable in size, so it seems a List<T> would be more appropriate here.

Code (csharp):

1. public List<GameObject> enemies;

With lists you just remove the item.

Code (csharp):

1. enemies.Remove( doomedEnemy);

In fact, if you want to remove all nulls or Destroyed objects (remember, destroyed things don't become destroyed until end of current frame), then all you need is:

Code (csharp):

1. enemies.RemoveAll( x => !x);

Means, "for all x that are not true, remove them," sort of a hinky-janky usage of a lambda and Unity's null boolean override thingy, but it works for anything derived from UnityEngine.Object.

 

If your code needs to be efficient, then you can create very simple event model. Without modifying arrays/lists and iterating through all of that in Update.

Code (CSharp):

1.  
2. public class Enemy : MonoBehaviour
3. {
4.     public event UnityAction Died;
5.  
6.     public void ApplyDamage()
7.     {
8.         Died?.Invoke();
9.     }
10. }
11.  
12. public class GameManager : MonoBehaviour
13. {
14.     public Enemy[] enemies;
15.  
16.     private float enemyCount;
17.  
18.     private void Awake()
19.     {
20.         enemyCount = enemies.Length;
21.     }
22.  
23.     private void OnEnable()
24.     {
25.         foreach(var enemy in enemies)
26.             enemy.Died += OnEnemyDied;
27.     }
28.  
29.     private void OnDisable()
30.     {
31.         foreach(var enemy in enemies)
32.             if (enemy != null)
33.                 enemy.Died -= OnEnemyDied;
34.     }
35.  
36.     private void OnEnemyDied()
37.     {
38.         enemyCount--;
39.         if (enemyCount == 0)
40.             SceneManager.LoadScene("Scene 3");
41.     }
42. }