Using ForEach Loop to change variables on prefabs

Hi all,

I have a bunch of instances of a prefab with a public boolean. I want to be able to change the boolean of all the instances on a click. Using a ForEach loop seemed the easiest way. I followed the code from the API site, but every time I try and play I get a "NullReferenceException: Object reference not set to an instance of an object" error. The code is below:

     private GameObject[] units;
 
     void Update () {
 
         // Left click to select unit
         if (Input.GetKeyDown(KeyCode.Mouse0))
         {
             units = GameObject.FindGameObjectsWithTag("unit1");
 
             foreach (GameObject Hunter in units)
             {
                 gameObject.GetComponent<unit1control>().active = false;
             }

The offending line is gameObject.GetComponent().active = false; - anyone have an idea of how to resolve this?

Thanks!