non c'è la parte del success
codice:
var getParties:Object = new LoadVars();
_global.partiesData = new Array();
function MyLoadVarsOnLoad(success) {
    if(success)
        tot = this["total"];
        if (tot<1) {
            trace("no data");
        } else {
            partiesData["total"] = this["total"];
            for (i=1; i<=tot ; i++) {
                partiesData["name_"+i] = this["name_"+i];
                trace(partiesData["name_"+i]);
            }
        }
    }
}
function LoadData() {
    getParties.load("http://localhost/prova_sito/web/local.php");
}
getParties.onLoad = MyLoadVarsOnLoad;
prova così