<script type="text/JavaScript"> <!--  function foc(){  document.getElementById("searchkey").focus();  }   //这是做搜索时一个函数与本文无关  function init(){  //初始化函数   if (history.dmenu){}else   {    history.dmenu=1;   } //如果history.dmenu没有定义则设置为１即显示首页按扭的效果   switch(history.dmenu){    case 1:     {     //alert(history.dmenu);     document.getElementById("d_id1").src="/images/anB1.gif";     document.getElementById("d_id2").src="/images/anB2.gif";     document.getElementById("d_id3").src="/images/anB3.gif";     document.getElementById("d_id4").src="/images/anB4.gif";     document.getElementById("d_id5").src="/images/anB5.gif";     document.getElementById("d_id6").src="/images/anB6.gif";     break;}     case 2:     {     //alert(history.dmenu);     document.getElementById("d_id1").src="/images/anB11.gif";     document.getElementById("d_id2").src="/images/anB22.gif";     document.getElementById("d_id3").src="/images/anB3.gif";     document.getElementById("d_id4").src="/images/anB4.gif";     document.getElementById("d_id5").src="/images/anB5.gif";     document.getElementById("d_id6").src="/images/anB6.gif";     break;     }     case 3:     {     document.getElementById("d_id1").src="/images/anB11.gif";     document.getElementById("d_id2").src="/images/anB2.gif";     document.getElementById("d_id3").src="/images/anB33.gif";     document.getElementById("d_id4").src="/images/anB4.gif";     document.getElementById("d_id5").src="/images/anB5.gif";     document.getElementById("d_id6").src="/images/anB6.gif";     break;     }     case 4:     {     document.getElementById("d_id1").src="/images/anB11.gif";     document.getElementById("d_id2").src="/images/anB2.gif";     document.getElementById("d_id3").src="/images/anB3.gif";     document.getElementById("d_id4").src="/images/anB44.gif";     document.getElementById("d_id5").src="/images/anB5.gif";     document.getElementById("d_id6").src="/images/anB6.gif";     break;     }     case 5:     {     document.getElementById("d_id1").src="/images/anB11.gif";     document.getElementById("d_id2").src="/images/anB2.gif";     document.getElementById("d_id3").src="/images/anB3.gif";     document.getElementById("d_id4").src="/images/anB4.gif";     document.getElementById("d_id5").src="/images/anB55.gif";     document.getElementById("d_id6").src="/images/anB6.gif";     break;     }     case 6:     {     document.getElementById("d_id1").src="/images/anB11.gif";     document.getElementById("d_id2").src="/images/anB2.gif";     document.getElementById("d_id3").src="/images/anB3.gif";     document.getElementById("d_id4").src="/images/anB4.gif";     document.getElementById("d_id5").src="/images/anB5.gif";     document.getElementById("d_id6").src="/images/anB66.gif";     break;     }   }  }  //上面是具体的判断那个变量然后据变量的值来进行图片的变换从而达到我们要的效果．  function menushow(d_id){   switch(d_id){    case 1:     history.dmenu=1;     break;    case 2:     history.dmenu=2;     break;    case 3:     history.dmenu=3;     break;    case 4:     history.dmenu=4;     break;    case 5:     history.dmenu=5;     break;    case 6:     history.dmenu=6;     break;   }  }  //按下相关图片按钮后设置history.dmenu为相应的值从而在页面加载时能根据这个值来进行图片的变换 //--> </script> <table width="960" border="0" align="center" cellpadding="0" cellspacing="0">   <tr>     <td height="57" colspan="4"><table width="100%" border="0" cellpadding="0" cellspacing="0">       <tr>         <td width="394" height="57" rowspan="2"><img src="/images/LOGO.gif" width="394" height="57" /></td>         <td width="134" height="43"> </td>         <td width="129" align="right" valign="middle"><a href="#"><img src="/images/anA1.gif" width="114" height="26" border="0" /></a></td>         <td width="97" align="right" valign="middle"><a href="#"><img src="/images/anA2.gif" width="78" height="26" border="0" /></a></td>         <td width="100" align="right" valign="middle"><strong><a href="#"><img src="/images/anA3.gif" width="75" height="26" border="0" /></a></strong></td>         <td width="92" align="right" valign="middle"><a href="#"><img src="/images/anA4.gif" width="70" height="26" border="0" /></a></td>         <td width="14" align="right" valign="middle"> </td>       </tr>       <tr>         <td colspan="6"> </td>       </tr>     </table></td>   </tr>   <tr>     <td colspan="4"><table width="100%" border="0" cellpadding="0" cellspacing="0">       <tr>         <td width="104"><a href="/"><img src="/images/anB1.gif" name="d_id1" width="103" height="28" border="0" id="d_id1" onClick="menushow(1)"/></a></td>         <td width="104" height="28"><a href="/order/"><img src="/images/anB2.gif" name="d_id2" width="104" height="28" / border="0" id="d_id2" onClick="menushow(2)"></a></td>         <td width="104"><a href="/news/"><img src="/images/anB3.gif" name="d_id3" width="104" height="28" border="0" id="d_id3" onClick="menushow(3)"/></a></td>           <td width="104"><a href="/law/"><img src="/images/anB6.gif" name="d_id4" width="104" height="28" border="0" id="d_id4"  onClick="menushow(4)"/></a></td>   <td width="104"><a href="/exhibit/"><img src="/images/anB4.gif" name="d_id5" width="104" height="28" border="0" id="d_id5" onClick="menushow(5)"/></a></td>         <td width="104"><a href="/company/"><img src="/images/anB5.gif" name="d_id6" width="104" height="28" border="0" id="d_id6" onClick="menushow(6)"/></a></td>         <td width="432" background="/images/bjB1.gif"> </td>         <td width="4"><img src="/images/tuB1.gif" width="4" height="28" /></td>       </tr>       <tr>         <td height="59" colspan="7"><table width="100%" border="0" cellpadding="0" cellspacing="0" background="/images/bjB2.gif" class="toptable">           <tr>             <td width="17%" height="58" align="center"> </td>             <td width="5%" align="center"><img src="/images/tuB4.gif" width="30" height="30" /></td>             <td width="4%" align="center"><span class="STYLE1"></span></td>             <td width="31%" align="center"><input name="searchkey" type="text" id="searchkey" size="40" /></td>             <td width="8%" align="center"><select name="select">               <option value="0">Please Select</option>               <option value="1">News</option>               <option value="2">Exhibit</option>               <option value="3">Company</option>             </select></td>             <td width="9%" align="center"><a href="#"><img src="/images/tuB5.gif" width="74" height="24" border="0" /></a></td>             <td width="10%" align="center" valign="middle"><img src="/images/tuB6.gif" width="3" height="5" />  <a href="javascript:void(0)" class="kfs" onClick="foc()">站内搜索</a></td>             <td width="16%"> </td>           </tr>         </table></td>       </tr>     </table></td>   </tr>   <tr>     <td width="6"><img src="/images/tuB2.gif" width="6" height="29" /></td>     <td width="46" align="center" background="/images/bjB3.gif"><strong>公告</strong></td>     <td width="904" background="/images/bjB3.gif"><a href="#" class="lan"> to trash cans, find the Public Utility Equipment </a><span class="STYLE2">new!</span><br /></td>     <td width="6" ><img src="/images/tuB3.gif" width="6" height="29" /></td>   </tr> </table> <script language="javascript"> init();   //这里注意一定要写在这里，要不然这个初始化函数就会报错说找不到对像 </script>

今天测试时发现了一个问题，得用上面写的方法时对ＩＥ不支持，在火狐上没有问题，所以对程序进行了下小修改．过程是这样的．对于ＩＥ浏览器使用session来判断，每按一个按钮时就写一个session("dmenu")为相应的值，然后把这个值写在页面的一个隐藏域里，然后在页面初始化时判断是使用的什么类型浏览器，如果是ＩＥ的就执行通过session来判断的函数，而这个session则是通过获取那个隐藏域里的值，而如果是非ＩＥ浏览器就运用上面我昨天写的也就是上面的init函数来进行．判断代码如下： <script language="javascript"> if(navigator.userAgent.indexOf("MSIE")>0){     init2();//是ＩＥ浏览器就执行这个  }else{   init();   //否则执行这个  } </script> 如此一来就完美的解决了这个问题．也许有朋友会说用session就可以了，但经过我的实验是用session火狐的根本不认，我也不知道什么原因，所以只好用我这个方法了．如果你有好方法请告诉我．