gistfile1.cs

    public class Config
    {
        public string Username { get; set; }
        public string Password { get; set; }

        public static readonly string CfgFilePath = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "anyhubdesktop.conf");

        public Config()
        {
        }

        public static Config Load()
        {
            if (!F.Exists(CfgFilePath))
                return new Config { Username = null };

            JavaScriptSerializer jss = new JavaScriptSerializer();
            return jss.Deserialize<Config>(F.ReadAllText(CfgFilePath));
        }

        public void Save()
        {
            JavaScriptSerializer jss = new JavaScriptSerializer();
            string json = jss.Serialize(this);
            F.WriteAllText(CfgFilePath, json);
        }
    }