function getQuerystring(key, default_)
{
    if (default_==null)
    {
        default_="";
    }
    var search = unescape(location.search);
    if (search == "")
    {
        return default_;
    }
    search = search.substr(1);
    var params = search.split("&");
    for (var i = 0; i < params.length; i++)
    {
        var pairs = params[i].split("=");
        if(pairs[0] == key)
        {
            return pairs[1];
        }
    }
    return default_;
}