NullReferenceException: Object reference not set to an instance of an object Enemys.Start () (at Ass

Error:
NullReferenceException: Object reference not set to an instance of an object
Enemys.Start () (at Assets/Scripts/Enemys.cs:15)

Enemys Code:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class Enemys : MonoBehaviour
6. {
7.     [SerializeField]
8.     private float _Speed = 4f;
9.  
10.     private Player _player;
11.  
12.     // Start is called before the first frame update
13.     void Start()
14.     {
15.          _player = GameObject.Find("Player").GetComponent<Player>();
16.     }
17.  
18.     // Update is called once per frame
19.     void Update()
20.     {
21.         transform.Translate(new Vector3(0, -1, 0) * _Speed * Time.deltaTime);
22.  
23.         if (transform.position.y <= -5.3f)
24.         {
25.             float randomX = Random.Range(-11f, 11f);
26.             transform.position = new Vector3(randomX, 7.1f, 0);
27.         }
28.     }
29.     private void OnTriggerEnter2D(Collider2D other)
30.     {
31.         if (other.tag == "Player")
32.         {
33.             Destroy(gameObject);
34.             Player player = other.transform.GetComponent<Player>();
35.  
36.             if (player != null)
37.             {
38.                 player.Damage();
39.             }
40.         }
41.         if (other.tag == "Laser")
42.         {
43.             Destroy(other.gameObject);
44.             //Add 10 to score
45.             if(_player != null)
46.             {
47.                 _player.Score();
48.             }
49.             Destroy(gameObject);
50.         }
51.     }
52. }
53.  

Player Code:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class Player : MonoBehaviour
6. {
7.     [SerializeField]
8.     private float _speed = 5f;
9.     private float _speedMultiplayer = 2;
10.     [SerializeField]
11.     private GameObject _laserPrefab;
12.     [SerializeField]
13.     private GameObject _tripleShot;
14.     [SerializeField]
15.     private float _fireRate = 0.5f;
16.     private float _nextFire = 0.0f;
17.     [SerializeField]
18.     private int _lives = 3;
19.  
20.     private bool _isSpeedBoostActive = false;
21.     private bool _isTripleShotActive = false;
22.     private bool _isShieldActive = false;
23.  
24.     [SerializeField]
25.     private int _score;
26.  
27.  
28.     [SerializeField]
29.     private GameObject _ShieldVisualizer;
30.  
31.     [SerializeField]
32.     private SpawnManager _spawnManager;
33.  
34.  
35.     void Start()
36.     {
37.      
38.         transform.position = new Vector3(0, 0, 0);
39.         _spawnManager = GameObject.Find("Spawn_Managr").GetComponent<SpawnManager>();
40.         if(_spawnManager == null)
41.         {
42.             Debug.LogError("no SpawnManager");
43.         }
44.     }
45.  
46.  
47.     void Update()
48.     {
49.         CalculateMovment();
50.         if (Input.GetKeyDown(KeyCode.Space) && Time.time > _nextFire)
51.           {
52.                 ShootLaser();
53.           }
54.  
55.     }
56.  
57.     void CalculateMovment()
58.     {
59.         float horizontalInput = Input.GetAxis("Horizontal");
60.         float verticalInput = Input.GetAxis("Vertical");
61.          transform.Translate(new Vector3(horizontalInput, verticalInput, 0) * (_speed*_speedMultiplayer) * Time.deltaTime);
62.  
63.         transform.position = new Vector3(Mathf.Clamp(transform.position.x,-10f,10f),transform.position.y, 0);
64.         transform.position = new Vector3(transform.position.x, Mathf.Clamp(transform.position.y,-4.13f,0), 0);
65.     }
66.  
67.  
68.     void ShootLaser()
69.     {
70.         _nextFire = Time.time + _fireRate;
71.         if (_isTripleShotActive == true)
72.         {
73.             Instantiate(_tripleShot, transform.position, Quaternion.identity);
74.         }
75.         else
76.         {
77.             Instantiate(_laserPrefab, transform.position + new Vector3(0, 1.04f, 0), Quaternion.identity);
78.         }
79.        
80.    
81.     }
82.  
83.  
84.     public void Damage()
85.     {
86.         if(_isShieldActive == true)
87.         {
88.             _isShieldActive = false;
89.             _ShieldVisualizer.SetActive(false);
90.             return;
91.         }
92.  
93.         _lives = _lives - 1;
94.         if (_lives< 1)
95.         {
96.             _spawnManager.OnPlayerDeath();
97.             Destroy(gameObject);
98.         }
99.     }
100.  
101.  
102.     public void TripleShotActive()
103.     {
104.         _isTripleShotActive = true;
105.  
106.         StartCoroutine(TripleShotPowerDownRoutine());
107.     }
108.  
109.     public void SpeedBoostActive()
110.     {
111.         _isSpeedBoostActive = true;
112.         _speed *= _speedMultiplayer;
113.         StartCoroutine(SpeedBoostDownRoutine());
114.     }
115.  
116.     public void ShieldActive()
117.     {
118.         _isShieldActive = true;
119.         _ShieldVisualizer.SetActive(true);
120.     }
121.  
122.  
123.     IEnumerator TripleShotPowerDownRoutine()
124.     {
125.         yield return new WaitForSeconds(5f);
126.         _isTripleShotActive = false;
127.     }
128.  
129.     IEnumerator SpeedBoostDownRoutine()
130.     {
131.         yield return new WaitForSeconds(10f);
132.         _speed /= _speedMultiplayer;
133.         _isSpeedBoostActive = false;
134.     }
135.  
136.     //Method to add 10 to score
137.     public void Score()
138.     {
139.         _score = _score + 10;
140.         Debug.Log("UP Score");
141.     }
142.     //Communicate with the UI to update the score
143. }
144.  

 

We need the Error as well, your title is cut

 

NullReferenceException: Object reference not set to an instance of an object
Enemys.Start () (at Assets/Scripts/Enemys.cs:15)

 

Does a GameObject with the name "Player" exist? If that cannot be found, then null.GetComponent would cause the exception. You could also just use FindObjectOfType to directly find the Player component you are looking for.

Instead of having every enemy that spawns use a Find() method (which is slow and should only be used for prototyping), you should approach this differently. The place that spawns Enemies probably knows about the Player. So it could set the reference to the spawned enemy instead of the enemy needing to search the entire scene graph.. again and again for every enemy spawned.

 

tanks

 

Code (CSharp):

1.  _player = GameObject.Find("Player").GetComponent<Player>()

Either he cannot find the GameObject of "Player" or he Component doesnt exist

 

Some notes on how to fix a NullReferenceException error in Unity3D
- also known as: Unassigned Reference Exception
- also known as: Missing Reference Exception

http://plbm.com/?p=221

The basic steps outlined above are:
- Identify what is null
- Identify why it is null
- Fix that.

Expect to see this error a LOT. It's easily the most common thing to do when working. Learn how to fix it rapidly. It's easy. See the above link for more tips.