public void load(string filePath)
        {
            Stream streamUser = File.Open(filePath, FileMode.Open);
            BinaryFormatter formatter = new BinaryFormatter();
            User tmp = (User)formatter.Deserialize(streamUser);

            this.login = tmp.login;
            this.nom = tmp.nom;
            this.prenom = tmp.prenom;
            this.avatar = tmp.avatar;

            streamUser.Close();
        }