public static Currency GetCurrency(this ISharedPreferences sharedPref, string key)
{
var cultureInfo = sharedPref.GetCultureInfo(key + CultureInfoSuffix);
sharedPref.CheckContains(key + NameSuffix);
var name = sharedPref.GetString(key + NameSuffix, "");
return(new Currency(name, cultureInfo));
}