Q583 How can I count the time in seconds that a checkbox is really checked?

<form name="myForm">
<input name="myCheckBox" type="checkbox">
<input name="totalTime" type="text">
</form>

<script language="JavaScript"><!--
function timer() {
    if (document.myForm.myCheckBox.checked != isitchecked) {
    // checkbox clicked
        isitchecked = document.myForm.myCheckBox.checked;
        now = new Date()
        if (isitchecked)
            starttime = now.getTime(); // now checked so reset starttime
        else
            document.myForm.totalTime.value = 0; // no longer checked so reset
    }
    else {
    // not clicked since last check
        if (isitchecked) {
        // still checked
            now = new Date();
            totaltime = now.getTime() - starttime; // totaltime in milliseconds that checkbox has been checked.
            document.myForm.totalTime.value = totaltime/1000/60; // time in minutes
        }
    }
    setTimeout('timer()',100);
}

var totaltime = 0;

document.myForm.totalTime.value = totaltime;

var isitchecked = document.myForm.myCheckBox.checked;

if (isitchecked) {
    now = new Date()
    starttime = now.getTime(); // if intial stae is check then set starttime
}

timer(); // start constant monitoring of checkbox
//--></script>