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)
 {
	 <!--最新评价 销售排行-->
 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;

 <!--广告图片-->
  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;
 
  <!--产品系列图片-->
  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";
document.getElementById("bbs_s12").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";
document.getElementById("bbs_s12").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";
document.getElementById("bbs_s12").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";
document.getElementById("bbs_s12").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";
document.getElementById("bbs_s12").style.display="none";
 break;
  case 12:
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="none";
document.getElementById("bbs_s12").style.display="block";
 break;
  
  <!--产品分类图片-->
  case 13:
document.getElementById("bbs_s13").style.display="block";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="none";
 break;
 case 14:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="block";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="none";
 break;
 case 15:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="block";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="none";
 break;
 case 16:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="block";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="none";
 break;
  case 17:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="block";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="none";
 break;
  case 18:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="block";
document.getElementById("bbs_s19").style.display="none";
 break;
  case 19:
document.getElementById("bbs_s13").style.display="none";
document.getElementById("bbs_s14").style.display="none";
document.getElementById("bbs_s15").style.display="none";
document.getElementById("bbs_s16").style.display="none";
document.getElementById("bbs_s17").style.display="none";
document.getElementById("bbs_s18").style.display="none";
document.getElementById("bbs_s19").style.display="block";
 break;
 
  <!--产品展示图片-->
  case 20:
document.getElementById("bbs_s20").style.display="block";
document.getElementById("bbs_s21").style.display="none";
document.getElementById("bbs_s22").style.display="none";
document.getElementById("bbs_s23").style.display="none";
document.getElementById("bbs_s24").style.display="none";
 break;
 case 21:
document.getElementById("bbs_s20").style.display="none";
document.getElementById("bbs_s21").style.display="block";
document.getElementById("bbs_s22").style.display="none";
document.getElementById("bbs_s23").style.display="none";
document.getElementById("bbs_s24").style.display="none";
 break;
 case 22:
document.getElementById("bbs_s20").style.display="none";
document.getElementById("bbs_s21").style.display="none";
document.getElementById("bbs_s22").style.display="block";
document.getElementById("bbs_s23").style.display="none";
document.getElementById("bbs_s24").style.display="none";
 break;
 case 23:
document.getElementById("bbs_s20").style.display="none";
document.getElementById("bbs_s21").style.display="none";
document.getElementById("bbs_s22").style.display="none";
document.getElementById("bbs_s23").style.display="block";
document.getElementById("bbs_s24").style.display="none";
 break;
  case 24:
document.getElementById("bbs_s20").style.display="none";
document.getElementById("bbs_s21").style.display="none";
document.getElementById("bbs_s22").style.display="none";
document.getElementById("bbs_s23").style.display="none";
document.getElementById("bbs_s24").style.display="block";
 break;
  <!--产品下面图片--> 
   case 25:
document.getElementById("bbs_s25").style.display="block";
document.getElementById("bbs_s26").style.display="none";
document.getElementById("bbs_s27").style.display="none";
document.getElementById("bbs_s28").style.display="none";
 break;
    case 26:
document.getElementById("bbs_s25").style.display="none";
document.getElementById("bbs_s26").style.display="block";
document.getElementById("bbs_s27").style.display="none";
document.getElementById("bbs_s28").style.display="none";
 break;
    case 27:
document.getElementById("bbs_s25").style.display="none";
document.getElementById("bbs_s26").style.display="none";
document.getElementById("bbs_s27").style.display="block";
document.getElementById("bbs_s28").style.display="none";
 break;
    case 28:
document.getElementById("bbs_s25").style.display="none";
document.getElementById("bbs_s26").style.display="none";
document.getElementById("bbs_s27").style.display="none";
document.getElementById("bbs_s28").style.display="block";
 break;
 }
}