var isStart=true;
var nn;
var tt;
var bPlay=new Image;
bPlay.src = "images/bu_pla.gif";
var bPause=new Image;
bPause.src = "images/bu_pau.gif";
nn=1;
setTimeout('change_img()',4000);
function resetPlay(){
isStart=true;
var e = document.getElementById("top_slider");
var a = e.getElementsByTagName("img");
for(i=0;i<a.length;i++){
 if(a[i].src == bPlay.src) a[i].src = bPause.src;
}
}
function playorpau(e){
if(e.src == "bu_pau.gif"){
e.src = bPlay.src ;
isStart = false;
}else{
e.src = bPause.src;
isStart = true;
}
}

function setFocus(i)
{
 if(tt) clearTimeout(tt);
 nn = i;
 selectLayer1(i);
 
}
function selectLayer1(i)
{
 switch(i)
 {
	 <!--Ê×Ò³×ó²à-->
 case 1:
document.getElementById("bbs_s1").style.display="block";
document.getElementById("bbs_s2").style.display="none";
 break;
case 2:
document.getElementById("bbs_s1").style.display="none";
document.getElementById("bbs_s2").style.display="block";
 break;
 <!--¾«²ÊÍƼö-->
 case 3:
document.getElementById("bbs_s3").style.display="block";
document.getElementById("bbs_s4").style.display="none";
document.getElementById("bbs_s5").style.display="none";
document.getElementById("bbs_s6").style.display="none";
 break;
 case 4:
document.getElementById("bbs_s3").style.display="none";
document.getElementById("bbs_s4").style.display="block";
document.getElementById("bbs_s5").style.display="none";
document.getElementById("bbs_s6").style.display="none";
 break;
 case 5:
document.getElementById("bbs_s3").style.display="none";
document.getElementById("bbs_s4").style.display="none";
document.getElementById("bbs_s5").style.display="block";
document.getElementById("bbs_s6").style.display="none";

 break;
 case 6:
document.getElementById("bbs_s3").style.display="none";
document.getElementById("bbs_s4").style.display="none";
document.getElementById("bbs_s5").style.display="none";
document.getElementById("bbs_s6").style.display="block";
 break;
 <!--ͼƬ-->
  case 7:
document.getElementById("bbs_s7").style.display="block";
document.getElementById("bbs_s8").style.display="none";
document.getElementById("bbs_s9").style.display="none";
document.getElementById("bbs_s10").style.display="none";
document.getElementById("bbs_s11").style.display="none";
 break;
 case 8:
document.getElementById("bbs_s7").style.display="none";
document.getElementById("bbs_s8").style.display="block";
document.getElementById("bbs_s9").style.display="none";
document.getElementById("bbs_s10").style.display="none";
document.getElementById("bbs_s11").style.display="none";
 break;
 case 9:
document.getElementById("bbs_s7").style.display="none";
document.getElementById("bbs_s8").style.display="none";
document.getElementById("bbs_s9").style.display="block";
document.getElementById("bbs_s10").style.display="none";
document.getElementById("bbs_s11").style.display="none";
 break;
 case 10:
document.getElementById("bbs_s7").style.display="none";
document.getElementById("bbs_s8").style.display="none";
document.getElementById("bbs_s9").style.display="none";
document.getElementById("bbs_s10").style.display="block";
document.getElementById("bbs_s11").style.display="none";
 break;
 case 11:
document.getElementById("bbs_s7").style.display="none";
document.getElementById("bbs_s8").style.display="none";
document.getElementById("bbs_s9").style.display="none";
document.getElementById("bbs_s10").style.display="none";
document.getElementById("bbs_s11").style.display="block";
 break;
 }
}