Unity / How to set Limit for enemy spawn?

Question

I managed to spawn enemies but they keep spawning. How can I set a limit to avoid from spawning unceasingly?

I've tried to add spawnLimit and spawnCounter but couldn't manage it to work.

var playerHealth = 100;     // Reference to the player's heatlh.
var enemy : GameObject;                // The enemy prefab to be spawned.
var spawnTime : float = 3f;            // How long between each spawn.
var spawnPoints : Transform[];         // An array of the spawn points this enemy can spawn from.


function Start ()
{
    // Call the Spawn function after a delay of the spawnTime and then continue to call after the same amount of time.
    InvokeRepeating ("Spawn", spawnTime, spawnTime);
}


function Spawn ()
{
    // If the player has no health left...
    if(playerHealth <= 0f)
    {
        // ... exit the function.
        return;
    }


    // Find a random index between zero and one less than the number of spawn points.
    var spawnPointIndex : int = Random.Range (0, spawnPoints.Length);

    // Create an instance of the enemy prefab at the randomly selected spawn point's position and rotation.
    Instantiate (enemy, spawnPoints[spawnPointIndex].position, spawnPoints[spawnPointIndex].rotation);
}

Answer 1

You can use this kind of counter:

int maxEnemies = 100;
int enemiyCounter = 0;

and in Spawn() add:

if(enemiyCounter < maxEnemies){
    Instantiate (enemy, spawnPoints[spawnPointIndex].position, spawnPoints[spawnPointIndex].rotation);
    enemyCounter++;
}

instead of

Instantiate (enemy, spawnPoints[spawnPointIndex].position, spawnPoints[spawnPointIndex].rotation);