need help - radio button

[mrjoka]

hi guys i have a work it was first implemented with the drop down list:
<select name="zoom" onChange="showM ap(this.form)">
<option value=7 <% if zoom = 7 then %>selected<% end if %>>Provincie
<option value=5 <% if zoom = 5 then %>selected<% end if %>>Regio
<option value=4 <% if zoom = 4 then %>selected<% end if %>>Stad
<option value=3 <% if zoom = 3 then %>selected<% end if %>>Buurt
<option value=2 <% if zoom = 2 then %>selected<% end if %>>Wijk
<option value=1 <% if zoom = 1 then %>selected<% end if %>>Straat
</select>

this is the javascript:

<script type="text/javascript" language="JavaS cript">
<!--
function showMap(frm){
location.href = "mapv2.asp?Site ID=<%=SiteID%>& client_id=<%ID& location_idLID& address=server& zoom=" + frm.zoom.option s[frm.zoom.Select edindex].value;
return false;
}
//-->
</script>
now i changed it to a radio button group but i do not know how to change the javascript for the zoom: + frm.zoom.option s[frm.zoom.Select edindex].value;
any help will be appreciate it.
thanks

[acoder]

Loop through the radio buttons and look for the radio button that is checked (checked == true) and get its value.