// --------------------------------------------------
function days_in_february(arg_year) {
  var arg_year = Number(arg_year);
  if (arg_year < 1000 || arg_year > 9999) {
    return false;
  }
  return (((arg_year % 4 == 0) && ((!(arg_year % 100 == 0)) || (arg_year % 400 == 0))) ? 29 : 28 );
}
// --------------------------------------------------
function get_file_ext(arg_filename) {
  var var_output = (/[.]/.exec(arg_filename)) ? /[^.]+$/.exec(arg_filename).toString() : undefined;
  return var_output;
}
// --------------------------------------------------
function go_to(arg_url) {
  window.location.href = arg_url;
}
// --------------------------------------------------
function is_date(arg_year, arg_month, arg_day) {
  var arr_days_month = new Array(0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);
  if (isNaN(arg_year) || arg_year < 1000 || arg_year > 9999) {
    return false;
  }
  if (isNaN(arg_month) || arg_month < 1 || arg_month > 12) {
    return false;
  }
  if (isNaN(arg_day) || arg_day < 1 || arg_day > arr_days_month[arg_month]) {
    return false;
  }
  if ((arg_month == 2) && (arg_day > days_in_february(arg_year))) {
    return false;
  }
  return true;
}
// --------------------------------------------------
function is_ie() {
  return navigator.appName.indexOf("Microsoft")!= -1;
}
// --------------------------------------------------
function trim(arg_string) {
  var var_reg_exp = /^\s*|\s*$/g;
  return arg_string.toString().replace(var_reg_exp, "");
}
// --------------------------------------------------