How do you write a Pauseable-Timer Script in Unity JavaScript?

Hey Guys,
I wondering how you would be able to make a Pauseable-Timer Unity.

I have a flashlight toggle script here:

var flashlight : boolean;

function Update () {
    if (Input.GetButtonDown("Fire2")) {
       GetComponent(Light).enabled = !GetComponent(Light).enabled;

	if (GetComponent(Light).enabled)
		flashlight = true;
		Debug.Log("Flashlight On");
		flashlight = false;
		Debug.Log("Flashlight Off");


I need to make a battery as a form as a GUIBox for the flashlight.
At the start of the game, it would start at 100% and drop down to 0% in 1 second intervals.
The player can switch off the flashlight which would pause the timer. (Time.deltaTime)
I know I could use Time.deltaTime
but I can’t find a way to pause it.
(P.S. I also need the player to find battery’s scattered along an asylum or house which would increase their battery life in the flashlight.)

Do this:

    if(timer < maxTimer)
        timer += Time.deltaTime;

It will only add to the timer when the flashlight is on.
This way you can then reset the timer like this: timer = 0; when a battery is picked or something. Also you would have to make the flashlight battery indicator work with the timer variable… for example:

maxTimer = 120;
indicator = (maxTimer - timer)/maxTimer*100;
print(indicator + "%");

or something like that…