var t = n = 0, count;
$(document).ready(function(){
	count=$("#banner_list a").length;
	$("#banner_list a:not(:first-child)").hide(); 
	$("#banner_info").html($("#banner_list a:first-child").find("img").attr('alt'));
	$("#banner_info").click(function(){window.open($("#banner_list a:first-child").attr('href'), "_blank")});
	$("#banner li").click(function() { 
		var i = $(this).text() - 1;//获取Li元素内的值，即1，2，3，4  n = i;           
		if (i >= count) return;
		$("#banner_info").html($("#banner_list a").eq(i).find("img").attr('alt'));
		$("#banner_info").unbind().click(function(){window.open($("#banner_list a").eq(i).attr('href'), "_blank")});
		$("#banner_list a").filter(":visible").fadeOut(500).parent().children().eq(i).fadeIn(1000); 
		document.getElementById("banner").style.background="";
		$(this).toggleClass("on");
		$(this).siblings().removeAttr("class");
	});
	t = setInterval("showAuto()", 4000);
	$("#banner").hover(function() { clearInterval(t) }, function() {
		t = setInterval("showAuto()", 4000);
	});
})
function showAuto() {
	n = n >= (count - 1) ? 0 : ++n;
	$("#banner li").eq(n).trigger('click');
}