var secondsLeft = 59;

function expireSession()
{
    obj = document.getElementById("sessionWarning");
    if(obj) obj.style.display = "block";
    setInterval('logoffCountdown()',1000);
    
}
function logoffCountdown()
{
        if (secondsLeft == 0)
            window.location='Logout.aspx?to=true'

        obj = document.getElementById("expirationCountdown");
        if(obj) obj.innerHTML = secondsLeft;
        secondsLeft--;

}