var intervalId = null;
function slideAd(id, nStayTime, sState, nMaxHth, nMinHth) {
    this.stayTime = nStayTime * 1000 || 3000;
    this.maxHeigth = nMaxHth || 200;
    this.minHeigth = nMinHth || 1;
    this.state = sState || "down";
    var obj = document.getElementById(id);
    if (intervalId != null) window.clearInterval(intervalId);
    function openBox() {
        var h = obj.offsetHeight;
        obj.style.height = ((this.state == "down") ? (h + 1) : (h - 30)) + "px";
        if (obj.offsetHeight > this.maxHeigth) {
            window.clearInterval(intervalId);
            intervalId = window.setInterval(closeBox, this.stayTime);
        }
        if (obj.offsetHeight < this.minHeigth) {
            window.clearInterval(intervalId);
            obj.style.display = "none";
        }
    }
    function closeBox() {
        slideAd(id, this.stayTime, "up", nMaxHth, nMinHth);
    }
    intervalId = window.setInterval(openBox, 2);
}