javascript如何输出计算结果？

<script   language= "javascript ">
function   jsq()
{
var   dy=document.myform.dy.value;
var   dr=document.myform.dr.value;
for   (var   i=0;i <myform.js.length;i++)
{      
var   e=myform.js[i];      
if   (e.checked)                              
js=e.value;
}
alert(dy+js+dr);//输出1+1，想让它输出1+1的和
document.myform.jg.value=Math.round(dy+js+dr);
}
</script>


<form   id= "myform "   name= "myform "   method= "post "   action= " ">
        <td   height= "50 "   align= "center "> <input   name= "dy "   type= "text "   id= "dy "   onKeyPress= "if((event.keyCode <48   ||   event.keyCode> 57)   &&   event.keyCode!=46   ||   /\.\d\d$/.test(value))event.returnValue=false; "/>
            <input   type= "radio "   name= "js "   value= "+ " <%   if   request.form( "js ")= "+ "   then   %>   checked= "checked " <%   end   if   %> /> ＋
            <input   name= "js "   type= "radio "   value= "- " <%   if   request.form( "js ")= "- "   or   request.form( "js ")= " "   then   %>   checked= "checked " <%   end   if   %>   /> －
            <input   type= "radio "   name= "js "   value= "* " <%   if   request.form( "js ")= "* "   then   %>   checked= "checked " <%   end   if   %> /> ×
            <input   type= "radio "   name= "js "   value= "/ " <%   if   request.form( "js ")= "/ "   then   %>   checked= "checked " <%   end   if   %> /> ÷
            <input   name= "dr "   type= "text "   id= "dr "   onKeyPress= "if((event.keyCode <48   ||   event.keyCode> 57)   &&   event.keyCode!=46   ||   /\.\d\d$/.test(value))event.returnValue=false; "/>
            <input   type= "button "   name= "Submit "   value= "计算 "   onClick= "jsq(); "   />
        ＝
        <input   name= "jg "   type= "text "   id= "jg "     onKeyPress= "if((event.keyCode <48   ||   event.keyCode> 57)   &&   event.keyCode!=46   ||   /\.\d\d$/.test(value))event.returnValue=false; "/>         </td>
        </form>

------解决方案--------------------
Number(var)
转换下
如果是整形还可以parseInt(var)
------解决方案--------------------
<script language= "javascript "&g