<script type="text/javascript">
var regiondb = new Object()
regiondb["africa"] = [{value:"102", text:"Cairo"},
                      {value:"88", text:"Lagos"},
                      {value:"80", text:"Nairobi"},
                      {value:"55", text:"Pretoria"}];
regiondb["asia"] = [{value:"30", text:"Ankara"},
                    {value:"21", text:"Bangkok"},
                    {value:"49", text:"Pechino"},
                    {value:"76", text:"New Delhi"},
                    {value:"14", text:"Tokyo"}];
regiondb["australia"] = [{value:"64", text:"Suva"},
                          {value:"12", text:"Sydney"}];
regiondb["europa"] = [{value:"11", text:"Atene"},
                      {value:"35", text:"Francoforte"},
                      {value:"3", text:"Londra"},
                      {value:"15", text:"Madrid"},
                      {value:"1", text:"Parigi"},
                      {value:"10", text:"Roma"},
                      {value:"6", text:"Stoccolma"},
                      {value:"97", text:"San Pietroburgo"}];
regiondb["noamer"] = [{value:"73", text:"Dallas"},
                      {value:"71", text:"Los Angeles"},
                      {value:"5", text:"New York"},
                      {value:"37", text:"Toronto"}];
regiondb["suamer"] = [{value:"65", text:"Buenos Aires"},
                      {value:"31", text:"Caracas"},
                      {value:"66", text:"Rio di Janeiro"}];
function setCities(chooser) {
    var newElem;
    var where = (navigator.appName == "Microsoft Internet Explorer") ? -1 : null;
    var cityChooser = chooser.form.elements["città"];
    while (cityChooser.options.length) {
        cityChooser.remove(0);
    }
    var choice = chooser.options[chooser.selectedIndex].value;
    var db = regiondb[choice];
    newElem = document.createElement("option");
    newElem.text = "Seleziona una città:";
    newElem.value = "";
    cityChooser.add(newElem, where);
    if (choice != "") {
        for (var i = 0; i < db.length; i++) {
            newElem = document.createElement("option");
            newElem.text = db[i].text;
            newElem.value = db[i].value;
            cityChooser.add(newElem, where);
        }
    }
}
</script>