protected void btnSubmit_Click(object sender, EventArgs e)
        {
            var userCredentials = new Credentials(txtName.Text, txtPassword.Text, int.Parse(txtAge.Text), txtEmail.Text);

            userCredentials.SaveCredentials(userCredentials);

            this.Controls.Clear();

            
        }
        public void SaveCredentials(Credentials credentials)
        {

            //StreamReader reader = new StreamReader("credentials.txt");



            using (StreamWriter writer = new StreamWriter(@"C:\Users\colog_000\Desktop\credentials.txt", true))
            {
                writer.WriteLine("Username: "******"Password: "******"Age: " + credentials.Age);
                writer.WriteLine("Email address: " + credentials.Email);
                writer.WriteLine();
            }

        }