時間format

function formatTime(sec) {
    if (sec == '')
        return "";
    sec = parseInt(sec);
    var hour = parseInt(sec / 3600);
    var min = parseInt(sec / 60);
    sec = sec % 60;
    return hour + ":" + (min < 10 ? '0' + min : min) + ":" + (sec < 10 ? '0' + sec : sec);
}