方舟单机怎么换新地图:关于网页制作的问题

<script language="javascript">
var nn;
nn=1;
setTimeout('change_img()',6000);
function change_img()
{
if(nn>4) nn=1
setTimeout('setFocus1('+nn+')',6000);
nn++;
tt=setTimeout('change_img()',6000);
}
function setFocus1(i)
{
selectLayer1(i);
}
function selectLayer1(i)
{
switch(i)
{
case 1:
document.getElementById("focusPic1").style.display="block";
document.getElementById("focusPic2").style.display="none";
document.getElementById("focusPic3").style.display="none";
document.getElementById("focusPic4").style.display="none";
break;
case 2:
document.getElementById("focusPic1").style.display="none";
document.getElementById("focusPic2").style.display="block";
document.getElementById("focusPic3").style.display="none";
document.getElementById("focusPic4").style.display="none";
break;
case 3:
document.getElementById("focusPic1").style.display="none";
document.getElementById("focusPic2").style.display="none";
document.getElementById("focusPic3").style.display="block";
document.getElementById("focusPic4").style.display="none";
break;
case 4:
document.getElementById("focusPic1").style.display="none";
document.getElementById("focusPic2").style.display="none";
document.getElementById("focusPic3").style.display="none";
document.getElementById("focusPic4").style.display="block";
break;
}
}
</script>
<div class="focusPic">
<div id="focusPic1" style="display: block;">
<div class="pic"><a href="http://2006.163.com/photoset/01UO0032/1694.html"><img src="http://cimg2.163.com/sports/2006/6/28/200606280553106fe9b.jpg" alt="齐达内再成高卢英雄 法国3-1西班牙晋级" width="400" height="250" border="0" /></a></div>
<div class="text"><h2><a href="http://2006.163.com/photoset/01UO0032/1694.html">齐达内再成高卢英雄 法国3-1西班牙晋级</a></h2>
<div class="num bg1">
<ul>
<li>1</li><li><a href="javascript:setFocus1(2);" target="_self">2</a></li><li><a href="javascript:setFocus1(3);" target="_self">3</a></li><li><a href="javascript:setFocus1(4);" target="_self">4</a></li>
</ul>
</div>
</div>
</div>
<div id="focusPic2" style="display: none;">
<div class="pic"><a href="http://2006.163.com/special/00321UAB/ronarldgoal14.html"><img src="http://cimg2.163.com/sports/2006/6/27/20060627235159cb22a.jpg" alt="肥罗首开记录 巴西3-0加纳晋级八强" width="400" height="250" border="0" /></a></div>
<div class="text"><h2><a href="http://2006.163.com/special/00321UAB/ronarldgoal14.html">肥罗首开记录 巴西3-0加纳晋级八强</a></h2>
<div class="num bg2">
<ul>
<li><a href="javascript:setFocus1(2);" target="_self">1</a></li><li>2</li><li><a href="javascript:setFocus1(3);" target="_self">3</a></li><li><a href="javascript:setFocus1(4);" target="_self">4</a></li>
</ul>
</div>
</div>
</div>
<div id="focusPic3" style="display: none;">
<div class="pic"><a href="http://2006.163.com/06/0627/01/2KJ95CM600321VAP.html"><img src="http://cimg2.163.com/sports/2006/6/27/20060627043736d4f18.jpg" alt="黄健翔为点球疯狂 激情嚎叫意大利万岁" width="400" height="250" border="0" /></a></div>
<div class="text"><h2><a href="http://2006.163.com/06/0627/01/2KJ95CM600321VAP.html">黄健翔为点球疯狂 激情嚎叫意大利万岁</a></h2>
<div class="num bg3">
<ul>
<li><a href="javascript:setFocus1(1);" target="_self">1</a></li><li><a href="javascript:setFocus1(2);" target="_self">2</a></li><li>3</li><li><a href="javascript:setFocus1(4);" target="_self">4</a></li>
</ul>
</div>
</div>
</div>
<div id="focusPic4" style="display: none;"></div > <!-- 广告投放代码代码 -->
<div class="clear"> </div>
</div>