Array index is out of range.

Questions & Answers
1

Hello i have almost finished my 2D mobile game but i have a very last issue stepping in my way that i can’t figure out the solution so i’m hoping that someone could help me.
Here is the code:

using UnityEngine;
using System.Collections;
using UnityEngine.UI;

public class collectDimonds : MonoBehaviour {

public static int dimonds = 0;
public int dimondValue = 1;

public Transform[] dimondSpawn;
public Image dimond;

public bool spawning = false;

// Use this for initialization
void Start () {
	dimonds = PlayerPrefs.GetInt ("Dimanti");

}

void OnTriggerEnter2D(Collider2D coll)
{
	if (coll.gameObject.tag == "Dimond") 
	{
	
		dimonds += dimondValue;
		Destroy(coll.gameObject);
		spawning = false;

		
	}
}
void Update()
{
	PlayerPrefs.SetInt("Dimanti", dimonds);
	if (!spawning) {

		Spawn();
	}

}

void Spawn () 
{
	
	spawning = true;
	
	
	Transform coinSpawns = dimondSpawn [Random.Range (0, dimondSpawn.Length)];
	Image coinPrefab = (Image)Instantiate (dimond, coinSpawns.position, coinSpawns.rotation);
	coinPrefab.transform.SetParent(GameObject.FindObjectOfType<Canvas>().gameObject.transform);
	
}

}

And the error says:

IndexOutOfRangeException: Array index is out of range.
collectDimonds.Spawn() (at Assets/scripts/collectDimonds.cs :54)

2

Hello, @Bondolero!

The problem is in this line: Transform coinSpawns = dimondSpawn [Random.Range (0, dimondSpawn.Length)];

The max range of Random.Range should be the length of array dimondSpawn subtracted by 1. Because you want the the last index of dimondSpawn.

So this should work:
Transform coinSpawns = dimondSpawn [Random.Range (0, dimondSpawn.Length - 1)];

Here’s a sample:

int[] intArray = new int[ 3 ] { 2, 4, 6 };

	void Update()
	{
		// Invalid. Error: IndexOutOfRangeException:
		// Array is out of range.
		Debug.Log( intArray[ intArray.Length ] );

		// Valid. Length of array subtracted by 1.
		Debug.Log( intArray[ intArray.Length - 1 ] );
	}