选择进行产品比较的脚本

<script LANGUAGE="JavaScript">
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tmp=readCookie("pro_str");
item_arr=tmp.split("###");
floatstr = "<table height=100% width=100% border=0 bgcolor='#ffffff'>"+
"<form method='post'  name='compare' target='_blank'>"+
"<tr><td align=center height=26><font color=red><strong>〖产品比较篮〗</strong></font></td></tr>"+
"<tr><td><center>"+
"";
for(key in item_arr){
if (key){
//元素形如：2132|我的产品测试
tmp_info_arr=item_arr[key].split("|");
pid  = tmp_info_arr[0];
names= tmp_info_arr[1];
if (pid && names){
ft = "<font color=red size=1>|</font><br><input type=button name=name value='"+names+"' onclick=\"del('"+pid+"','"+names+"')\" style='border:1px solid;border-color:red ;background-color:white;height:24;width:150;cursor:hand;color:'black';'><input type='hidden' name='pro_id[]' value='"+pid+"'><br>";
floatstr = floatstr+ft;}}}
floatstr = floatstr + "<input type='hidden' name='subcatid' value='"+readCookie("subcat")+"'><br>&nbsp;&nbsp;&nbsp;<a href='#' href_cetemp='#' href_cetemp='#' onclick='empty()'><font color=blue>清空</font></a> &nbsp;&nbsp;<a href=# onclick='hide_layer(float)'><font color=blue>隐藏</font></a></center></td></tr>"+
"<tr><td align=center><input type='button' value='产品比较' name='submits'  onclick=\"comparecheck('bijiao.asp');\" style='cursor:hand;width:100px'>"+
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function comparecheck(url){
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mark++;}}
if(mark<2){
alert ('系统提示：请至少选择两款产品进行比较！！！\r\n选择方法：点击对应产品名称前的选择框即可添加该产品到产品对比篮。\r\n删除方法：点击比较篮中的产品名称即可完成去除比较篮中相应的产品。 '); }
else{
obj.submit();}}
//pro_str:产品字符串
//subcat :子类字符串
function change_select(pid,name){
//读出产品串后用函数返回一个数组
tmp=readCookie("pro_str");
//alert(tmp+"=="+pid+"==="+tmp.indexOf(pid));
if (tmp.indexOf(pid)!=-1){
del(pid,name);}
else{
add(pid,name);}}
function add(pid,names){
//读出产品串后用函数返回一个数组
tmp=readCookie("pro_str");
//检查数组的个数（即选择产品的个数）
tmp_arr=stringToArray(tmp,"###");
if (tmp_arr.length<5){
//看是否有相同的产品已被选择
//alert(tmp+"=="+pid+"==="+tmp.indexOf(pid));
if (tmp.indexOf(pid)!=-1){
alert("（"+names+"）已经被选择了！！！");}
else{
writeCookie("pro_str",tmp+pid+"|"+names+"###");}}
else{
alert("对不起，您只能一次最多选择4款产品进行比较！！！");}
redraw();
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writeCookie("pro_str",tmp.replace(pid+"|"+name+"###"));
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</script>
<INPUT  onclick="javascript:change_select(208,'3M固体水晶蜡')"type=checkbox>
<INPUT  onclick="javascript:change_select(150,'高尔夫球筒')" type=checkbox>