How to make a function stop when all the Gameobjects from the array are in the Game?

Hi everybody !

I'm making a little game with 2D objects (box, square, circles, etc...) appearing when I click. I have this code actually making things work : everytime I use the mouseclick a Gameobject is created from the array list in the inspector.

     //Changed to an array of objects assign as many as you have in inspector
     var boxes : GameObject[];
     var boxCounter : int;
      
     function Update()
     {
     if(Input.GetMouseButtonDown(0))//Checks to see if left mouse button was clicked.
     {
     CreateBox();
     }
     }
      
     function CreateBox()
     {
     var mousePos : Vector2 = Input.mousePosition;
      
     //Depth you want the center of the object to be is z which I used zero
     var boxPos : Vector3 = camera.ScreenToWorldPoint(mousePos.x, mousePos.y, 0);
      
     //I used the perfab box's rotation here but you can enter what you'd like as a euler using Quaternion.Euler(x,y,z)
     Instantiate(boxes[boxCounter], boxPos, boxes[boxCounter].transform.rotation);
      
     //This will increment if there are more boxes or reset to 0 if it is the last one.
     if(boxCounter == boxes.length-1)
     {
     boxCounter = 0;
     }else{
     boxCounter ++;
     }
     }

But now I have a little problem with the last part, the boxCounter. I want another function to start when all the GameObjects in the array are on the game screen. For example, "If boxcounter = number of array {function GamEnding()} else boxcounter ++" ; I don't want the counter to restart at 0 as the last function is working atm. I tried a few things but nothing worked well. Any idea?