状态栏里的动态欢迎语

<script type = "text/javascript">
var POSITION = 100;
var DELAY = 5;
var MESSAGE = "欢迎光临! Welcome to WWW.HELPOR.NET ";
var scroll = new statusMessageObject();

 function statusMessageObject(p, d)
{
    this.msg = MESSAGE;
	this.out = " ";
    this.pos = POSITION;
	this.delay = DELAY;
	this.i = 0;
	this.reset = clearMessage;
}

function clearMessage()
{
    this.pos = POSITION;
}

function scroller()
{
    for (scroll.i = 0; scroll.i < scroll.pos; scroll.i++)
    {
        scroll.out += " ";
    }
    if (scroll.pos >= 0) {
	scroll.out += scroll.msg;
	}
    else {
	scroll.out = scroll.msg.substring(-scroll.pos, scroll.msg.length);
	}
    window.status = scroll.out;
	scroll.out = " ";
    scroll.pos--;
    if (scroll.pos < -(scroll.msg.length))
    {
        scroll.reset();
    }
    setTimeout('scroller()', scroll.delay);
}

function snapIn(jumpSpaces, position)
{
    var msg = scroll.msg;
    var out = "";
    for (var i = 0; i < position; i++)
    {
        out += msg.charAt(i);
    }
    for (i = 1; i < jumpSpaces; i++)
    {
        out += " ";
    }
    out += msg.charAt(position);
    window.status = out;
    if (jumpSpaces <= 1)
    {
        position++;
        if (msg.charAt(position) == ' ')
        {
            position++;
        }
        jumpSpaces = 100 - position;
    }
    else if (jumpSpaces > 3)
    {
        jumpSpaces *= .75;
    }
    else
    {
        jumpSpaces--;
    }
    if (position != msg.length)
    {
        var cmd = "snapIn(" + jumpSpaces + "," + position + ")";
        scrollID = window.setTimeout(cmd, scroll.delay);
    }
    else
    {
        window.status = "";
        jumpSpaces = 0;
		position = 0;
		cmd = "snapIn(" + jumpSpaces + "," + position + ")";
        scrollID = window.setTimeout(cmd, scroll.delay);
        return false
    }
    return true
}
snapIn(100, 0);
</script>