高手请教select自动选择问题

<html>
<head>
<title></title>
<script language="javascript">
//关于缩进的变量定义
var prefixIndent = "--";
var prefixPrefix = String.fromCharCode(160,160);//从一组Unicode编码返回一个字符串，此处为返回由两个空格组成的字符串。//清空下拉框
function fnClearCombo(objCombo){
var i,intLen;
if(objCombo.Proced ==1){
intLen=objCombo.options.length;
for(i=0;i<intLen-objCombo.FirstIdx;i++) objCombo.options[objCombo.FirstIdx]=null;
}
else{
objCombo.FirstIdx=objCombo.options.length;
objCombo.Proced =1;
}
}
function findArrIndex(optionV,arrItems){
     var indexArr;
 for(var i=0;arrItems[i];i++)
      if(arrItems[i][0]==optionV) {indexArr=i;break;}
 return indexArr;
}/*************************************** 联动下拉框 ***************************************/
//subLevel:显示的子项层数
//         0--不显示任何子项；1--显示1层子项；2--显示2层子项...
//self    :是否显示当前项，即是否在子下拉框里显示父下拉框的当前选项
//         1--显示
//objCombo:父下拉框     objSubCombo:子下拉框     arrSubItems:二维数组名     strDefValue：默认选中项的id
function fnSetPositionVac(objCombo,objSubCombo,arrSubItems,subLevel,self,strDefValue,submessage){
  var message=submessage;
  var i;
  var bFound;
  var oOption;
  var pre=(self==1)?(prefixPrefix+prefixIndent):'';//如果形参self的值为1（即要在子下拉框中显示当前的父选项），则定义子选项的前缀pre为“  --”  fnClearCombo(objSubCombo);//清空子下拉框的值  bFound=false;
  
  if(!objCombo.disabled){
      var num = 0;
      for(i=0;i<objCombo.length;i++) if(objCombo.options[i].value==objCombo.value){num=i;break;}
      var arrIndex = findArrIndex(objCombo.options[num].value,arrSubItems);
  
     /*if(self==1 && parseFloat(arrIndex)>=0){
        var newoptiontext = (objSubCombo.size>1)?arrSubItems[arrIndex][2].replace(/中国/g,'全国'):arrSubItems[arrIndex][2];
oOption = new Option(newoptiontext,arrSubItems[arrIndex][0]);
        objSubCombo.options[objSubCombo.length] = oOption;
    if(strDefValue + "" == oOption.value + "") oOption.selected=true;
     }*/
  
     if(subLevel>0) bFound = fnAddSubItems(objCombo.options[num].value,objSubCombo,arrSubItems,strDefValue,pre,subLevel-1,submessage);
  }  /*if(!bFound && objSubCombo.options.length == 0){objSubCombo.disabled=true;if(parseFloat(objSubCombo.size)<=1) objSubCombo.style.display='none';} //如果 objSubCombo 的 size>1 则始终不隐藏
  else{objSubCombo.disabled=false;objSubCombo.style.display='';if(objSubCombo.selectedIndex<0) objSubCombo.selectedIndex=0;} //默认选中第一个option(如果strDefValue为null)*/
  if(!bFound && (objSubCombo.options.length == 0 || (objSubCombo.options.length == 1&&objSubCombo.options[0].text.indexOf('选择')>-1))) objSubCombo.disabled = true;
  else objSubCombo.disabled = false;
  if(objSubCombo.size>1) objSubCombo.style.display = '';
  else{
  if(objSubCombo.options.length<1) objSubCombo.style.display = 'none';
  else objSubCombo.style.display = '';
  }
  
  if(objSubCombo.onchange) objSubCombo.onchange();
}
function fnAddSubItems(pId,objSubCombo,arrSubItems,strDefValue,strPre,subLevel,m){
  var n=m;
  var i,j,oOption;
  var bFound=false;
  var text,value;
  var level = subLevel;
  
  for(i=0;i<arrSubItems.length;i++)
   if(arrSubItems[i][1] + "" == pId + ""){
text =  strPre + arrSubItems[i][2];
value = arrSubItems[i][0];//if(!bFound && objSubCombo.size<=1) objSubCombo.options[objSubCombo.length] = new Option('','');oOption = new Option(text,value);
objSubCombo.options[objSubCombo.length] = oOption;
if(strDefValue + "" == oOption.value + "") oOption.selected=true;
bFound = true;if(level>0) fnAddSubItems(arrSubItems[i][0],objSubCombo,arrSubItems,strDefValue,prefixPrefix+((strPre=='')?prefixIndent:strPre),level-1)
   }
  
  if(objSubCombo.options[0].value==''){
  if(pId=='') objSubCombo.options[0].text='请选择';
  else objSubCombo.options[0].text='不限';
  }
  
  return bFound;
}
/*************************************** end 联动下拉框 ***************************************/
</script>
<script language="javascript" type="text/javascript">
<!--
var arrBooktype=[
['gongju','0','工具书'],
['sanwenxiaoshuo','0','散文小说'],
['jiaocai','0','教材'],
['001','gongju','新华词典'],
['002','gongju','最新新华字典'],
['003','gongju','现代成语辞典'],
['004','gongju','辞海'],
['005','gongju','中英双语词典'],['001','sanwenxiaoshuo','朱自清散文集'],
['002','sanwenxiaoshuo','鲁迅文集'],
['003','sanwenxiaoshuo','呐喊'],
['004','sanwenxiaoshuo','告别夹边沟'],['001','jiaocai','ASP程序设计'],
['002','jiaocai','计算机应用基础'],
['003','jiaocai','会计原理'],
['004','jiaocai','毛泽东思想'],
['005','jiaocai','法律基础']
]function fnOnload(){
fnSetPositionVac(document.frmMain.booktype,document.frmMain.bookname,arrBooktype,1,0);
}
window.onload = fnOnload;
//-->
</script>
</head><body>
<form name="frmMain" method="get" action="">
请选择图书名称：<select name="booktype" onChange="fnSetPositionVac(this,this.form.bookname,arrBooktype,1,1,0)" style="width:200px">
  <option value="">请选择图书类别</option>
  <option value="gongju">工具书</option>
  <option value="sanwenxiaoshuo">散文小说</option>
  <option value="jiaocai">教材</option>
</select>
<select name="bookname" style="width:200px">
  <option value="">请选择图书名称</option>
</select>
</form>
</body>
</html>
yiran5467，如果我下面改成动态的，
['001','gongju','新华词典'],
['002','gongju','最新新华字典'],
['003','gongju','现代成语辞典'],
['004','gongju','辞海'],
['005','gongju','中英双语词典'],亦即：
<%
   if(nationStdList!= null && nationStdList.size()>0){
   for(int i=0;i<nationStdList.size();i++){
   UsertagVO nationStd = (UsertagVO)nationStdList.get(i);
%>
['00<%=i+1%>','国际标准','<%=nationStd.getUsertagName()%>'],
<%}%>为什么不可以，我该怎么改？