Object.operator ==

Parameters

Description

Compares two object references to see if they refer to the same object.

var target : Collider;
function OnTriggerEnter (trigger : Collider) {
    if (trigger == target)
        print("We hit the target trigger");
}

using UnityEngine;

public class Example : MonoBehaviour
{
    public Collider target;
    void OnTriggerEnter(Collider trigger)
    {
        if (trigger == target)
        {
            print("We hit the target trigger");
        }
    }
}

Get early out if there is no target.

var target : Transform;
function Update () {
    // Early out if the target is gone
    if (target == null)
        return;
}

using UnityEngine;

public class Example : MonoBehaviour
{
    public Transform target;
    void Update()
    {
        // Early out if the target is gone
        if (target == null)
        {
            return;
        }
    }
}

Be careful when comparing with null.

e.g.

GameObject go = new GameObject();
Debug.Log (go == null); // false

Object obj = new Object();
Debug.Log (obj == null); // true

using UnityEngine;

public class Example : MonoBehaviour
{
    void Start()
    {
        GameObject go = new GameObject();
        Debug.Log(go == null); // false

        Object obj = new Object();
        Debug.Log(obj == null); // true
    }
}

Instatiating a GameObject adds it to the scene so it's completely initialized (!destroyed). Instantiating a simple UnityEngine.Object has no such semantics, so the it stays in the 'destroyed' state which compares true to null.