检查数组的所有对象是否同时处于活动状态 Unity C#

Question

I've tried to make a script that if all the lights in my scene tagged "Light" are active at the same time, the game proceeds. None of the answers I've found have helped so far. I always end up with it only scanning the active objects, just randomly jumping out of the loop, or stopping when it has found one object that's active. Here is a simple piece of code that should have worked according to other posts

    void Update()
    {
        bool allActive = false;
        GameObject[] allLights = GameObject.FindGameObjectsWithTag("Light");
        if(currenObjective > 0 && currenObjective < 3)
        {
            for (int i = 0; i < allLights.Length; i++)
            {
                if (allLights[i].activeInHierarchy)
                {
                    allActive = true;
                    break;
                }
            }
            if (allActive)
            {
                currentObjective = 2;
            }
        }
    }

This code just sets the allActive variable to true at the moment one light is turned on.

Answer 1

You would need to invert the check:

private void Update()
{
    // Since Find is always a bit expensive I would do the cheapest check first
    if(currenObjective > 0 && currenObjective < 3)
    {
        var allLights = GameObject.FindGameObjectsWithTag("Light");
        var allActive = true;
        for (int i = 0; i < allLights.Length; i++)
        {
            if (!allLights[i].activeInHierarchy)
            {
                allActive = false;
                break;
            }
        }
        if (allActive)
        {
            currentObjective = 2;
        }
    }
}

---

Or You can do this in one line using Linq All

using System.Linq;

...

private void Update()
{
    // Since Find is always a bit expensive I would do the cheapest check first
    if(currenObjective > 0 && currenObjective < 3)
    {
        var allLights = GameObject.FindGameObjectsWithTag("Light");

        if (allLights.All(light => light.activeInHierarchy))
        {
            currentObjective = 2;
        }
    }
}

---

As a general note: You should avoid using FindGameObjectsWithTag every frame! Either store these references ONCE at start, or if you spawn more lights on runtime implement it event driven and add the newly spawned lights to a list and then use that list to check.

Answer 2

If i understant you want to know if all objects are active: using Linq does the job

you have to add using system.Linq to your script.

    GameObject[] allLights = GameObject.FindGameObjectsWithTag("Light");
    bool result = allLights.All(p => p.activeInHierarchy);

you could simplify your code like this:

private void Update()
{
    if(currenObjective > 0 && currenObjective < 3 && GameObject.FindGameObjectsWithTag("Light").All(p => p.activeInHierarchy))
    {
        currentObjective = 2;
    }
}

As says derHugo, FindGameObjectsWithTag is very expensive in each frame...