重置JavaScript计数器？

Question

I am trying to program a counter into a website via JavaScript and have found exactly what I need here: http://www.w3schools.com/js/js_timing.asp

What I am trying to do is count down from 30 to 0. Once the counter reaches zero I want to display an alert. I have been able to get this to work. The only function that I cannot figure out is how to reset my counter back to 30 on a certain button push. I have tried code such as document.gameForm.txt.value=30; but for whatever reason 30 does not replace whatever text is currently in the box.

Answer 1

As far as I understand it, you need to call clearTimeout() function to reset the counter eg:

var t = setTimeout("alert('I am displayed after 3 seconds!')", 3000);

Later you can reset it like:

clearTimeout(t);