Nulll Reference Problem with my missile script when all target is being Destroy

Scripting
1

I have a missile script where i look for a target and then chase toward it but, after the target was remove the script giving me this error

NullReferenceException: Object reference not set to an instance of an object
Missile.FindClosestEnemy () (at Assets/Scripts/Player_Scripts/Missile.cs:63)
Missile.Start () (at Assets/Scripts/Player_Scripts/Missile.cs:19)

{



    public string searchTag;
    private GameObject closetMissile;
    public Transform target;
    public GameObject missileExpObject;
    public int _dmg;

    void Start ()
    {
        closetMissile = FindClosestEnemy ();
        if (closetMissile)
            target = closetMissile.transform;



        //if (target == null) {
        //    Destroy (this.gameObject);
            //transform.position = Vector3.up * 10f * Time.deltaTime;

    //    } else {
       
       
        //}
    }

    void Update ()
    {


        if (target != null) {
            Vector3 dir = target.transform.position - transform.position;
            float angle = Mathf.Atan2 (dir.y, dir.x) * Mathf.Rad2Deg - 90;
            transform.rotation = Quaternion.AngleAxis (angle, Vector3.forward);
            //transform.Translate (Vector3.forward * 5.0f * Time.deltaTime);
            Rigidbody rig = GetComponent<Rigidbody> ();
            rig.velocity = transform.position = Vector3.MoveTowards (transform.position, target.transform.position, 10f * Time.deltaTime);
   
        } else {
           
           
        }

    }

    GameObject FindClosestEnemy ()
    {
        GameObject gos;
        gos = GameObject.FindGameObjectWithTag (searchTag);

        GameObject closest = null;
        float distance = Mathf.Infinity;

        Vector3 position = transform.position;
            Vector3 diff = gos.transform.position - position;
            float curDistance = diff.sqrMagnitude;

            if (curDistance < distance) {
                closest = gos;
                distance = curDistance;
            }

        return closest;
    }
2

My guess would be that you’re only setting the target on Start() which runs once, so it will find closest target and then when that target it destroyed it gives a null reference. You are also returning a null object in your “FindClosestEnemy()” method, you are returning a gameobject called “closest” but the value is always null. You may want to try something like this to make things a little simpler:

private bool IsInRange()
{
    return Vector3.Distance(target.position, missile.position) < distance;
}

Hope this helps

-Joshmond

3

If gos doesn’t find anything with that tag, it will be null. Thus, most likely your error as you try to access it’s transform even if it doesn’t exist.

4

when i add return null or if(object != null) FindClosestEnemy();