滚动的公告栏的实现

<script type="text/javascript"><!--google_ad_client = "pub-2947489232296736";/* 728x15, 创建于 08-4-23MSDN */google_ad_slot = "3624277373";google_ad_width = 728;google_ad_height = 15;//--></script><script type="text/javascript"src="http://pagead2.googlesyndication.com/pagead/show_ads.js"></script>

<script type="text/javascript"><!--google_ad_client = "pub-2947489232296736";/* 160x600, 创建于 08-4-23MSDN */google_ad_slot = "4367022601";google_ad_width = 160;google_ad_height = 600;//--></script><script type="text/javascript"src="http://pagead2.googlesyndication.com/pagead/show_ads.js"></script>

<script language="JavaScript1.2"> 

//设置下面的三行参数，分别是宽度、高度和背景色。 
var scrollerwidth=150 
var scrollerheight=60 
var scrollerbgcolor='white' 

//下面设置显示的文字内容，可以使用标准的HTML语法。 
var messages=new Array() 
messages[0]="<a href='../index.html'>点这里回首页，欢迎你访问小耗子的《三招两式》</a>" 
messages[1]="<a href='../download/index.htm'>点这里去下载中心，你可以到那里下载本站各个栏目的压缩包</a>" 
messages[2]="<a href='../tip/index.htm'>点这里去心得技巧栏目，这里搜集了网页制作高手们的心得文章</a>" 
messages[3]="<a href='../search/index.htm'>点这里去本站搜索，快速检索本站内容</a>" 
messages[4]="<a href='../connect.htm'>点这里联系小耗子，有任何意见建议请来信。</a>" 

//下面的代码不要改动 

if (messages.length>1) 
i=2 
else 
i=0 

function move1(whichlayer){ 
tlayer=eval(whichlayer) 
if (tlayer.top>0&&tlayer.top<=5){ 
tlayer.top=0 
setTimeout("move1(tlayer)",3000) 
setTimeout("move2(document.main.document.second)",3000) 
return 
} 
if (tlayer.top>=tlayer.document.height*-1){ 
tlayer.top-=5 
setTimeout("move1(tlayer)",100) 
} 
else{ 
tlayer.top=scrollerheight 
tlayer.document.write(messages[i]) 
tlayer.document.close() 
if (i==messages.length-1) 
i=0 
else 
i++ 
} 
} 

function move2(whichlayer){ 
tlayer2=eval(whichlayer) 
if (tlayer2.top>0&&tlayer2.top<=5){ 
tlayer2.top=0 
setTimeout("move2(tlayer2)",3000) 
setTimeout("move1(document.main.document.first)",3000) 
return 
} 
if (tlayer2.top>=tlayer2.document.height*-1){ 
tlayer2.top-=5 
setTimeout("move2(tlayer2)",100) 
} 
else{ 
tlayer2.top=scrollerheight 
tlayer2.document.write(messages[i]) 
tlayer2.document.close() 
if (i==messages.length-1) 
i=0 
else 
i++ 
} 
} 

function move3(whichdiv){ 
tdiv=eval(whichdiv) 
if (tdiv.style.pixelTop>0&&tdiv.style.pixelTop<=5){ 
tdiv.style.pixelTop=0 
setTimeout("move3(tdiv)",3000) 
setTimeout("move4(second2)",3000) 
return 
} 
if (tdiv.style.pixelTop>=tdiv.offsetHeight*-1){ 
tdiv.style.pixelTop-=5 
setTimeout("move3(tdiv)",100) 
} 
else{ 
tdiv.style.pixelTop=scrollerheight 
tdiv.innerHTML=messages[i] 
if (i==messages.length-1) 
i=0 
else 
i++ 
} 
} 

function move4(whichdiv){ 
tdiv2=eval(whichdiv) 
if (tdiv2.style.pixelTop>0&&tdiv2.style.pixelTop<=5){ 
tdiv2.style.pixelTop=0 
setTimeout("move4(tdiv2)",3000) 
setTimeout("move3(first2)",3000) 
return 
} 
if (tdiv2.style.pixelTop>=tdiv2.offsetHeight*-1){ 
tdiv2.style.pixelTop-=5 
setTimeout("move4(second2)",100) 
} 
else{ 
tdiv2.style.pixelTop=scrollerheight 
tdiv2.innerHTML=messages[i] 
if (i==messages.length-1) 
i=0 
else 
i++ 
} 
} 

function startscroll(){ 
if (document.all){ 
move3(first2) 
second2.style.top=scrollerheight 
} 
else if (document.layers){ 
move1(document.main.document.first) 
document.main.document.second.top=scrollerheight+5 
document.main.document.second.visibility='show' 
} 
} 

window.onload=startscroll 

</script> 
<ilayer id="main" width=&{scrollerwidth}; height=&{scrollerheight}; bgcolor=&{scrollerbgcolor};> 
<layer id="first" left=0 top=1 width=&{scrollerwidth};> 
<script language="JavaScript1.2"> 
if (document.layers) 
document.write(messages[0]) 
</script> 
</layer> 
<layer id="second" left=0 top=0 width=&{scrollerwidth}; visibility=hide> 
<script language="JavaScript1.2"> 
if (document.layers) 
document.write(messages[1]) 
</script> 
</layer> 
</ilayer> 
<script language="JavaScript1.2"> 
if (document.all){ 
document.writeln('<span id="main2" style="position:relative;width:'+scrollerwidth+';height:'+scrollerheight+';overflow:hiden;background-color:'+scrollerbgcolor+'">') 
document.writeln('<div style="position:absolute;width:'+scrollerwidth+';height:'+scrollerheight+';clip:rect(0 '+scrollerwidth+' '+scrollerheight+' 0);left:0;top:0">') 
document.writeln('<div id="first2" style="position:absolute;width:'+scrollerwidth+';left:0;top:1;">') 
document.write(messages[0]) 
document.writeln('</div>') 
document.writeln('<div id="second2" style="position:absolute;width:'+scrollerwidth+';left:0;top:0">') 
document.write(messages[1]) 
document.writeln('</div>') 
document.writeln('</div>') 
document.writeln('</span>') 
} 
</script>  <script type="text/javascript"><!--google_ad_client = "pub-2947489232296736";/* 728x15, 创建于 08-4-23MSDN */google_ad_slot = "3624277373";google_ad_width = 728;google_ad_height = 15;//--></script><script type="text/javascript"src="http://pagead2.googlesyndication.com/pagead/show_ads.js"></script>

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