protected void logInButton_Click(object sender, EventArgs e)
    {
        Session["User"] = logUsernameTextBox.Text;
        bool successfulLogin = false;

        string userFilePath = Server.MapPath("~") + "/App_Data/userFile.txt";
        string[] userArray = File.ReadAllLines(Server.MapPath("~") + "/App_Data/userFile.txt");


        for (int i = 0; i < userArray.Length; i++)
        {
            //Split username password
            string[] userPasswordPair = userArray[i].Split(' ');


            //if username and password given match any user pair

            if (userPasswordPair[0] == logUsernameTextBox.Text && userPasswordPair[1] == logPasswordTextBox.Text)
            {
                successfulLogin = true;
            }

        }
        // if the username and password match a set in the file then successful login
        if (successfulLogin == true)
        {
            Response.Write("Successful Login");
            Session["User"] = logUsernameTextBox.Text;
            Response.Redirect("TuitterDisplay.aspx");
        }
        //if username and password did not match set
        else if (successfulLogin == false)
        {
            Response.Write("Unsuccessful Login");
            logErrorLabel.Text = ("Unsuccessful Login");
        }
    }
    protected void signUpButton_Click(object sender, EventArgs e)
    {

        bool successfulLogin = false;

        string userFilePath = Server.MapPath("~") + "/App_Data/userFile.txt";
        string[] userArray = File.ReadAllLines(Server.MapPath("~") + "/App_Data/userFile.txt");


        for (int i = 0; i < userArray.Length; i++)
        {
            //Split username password
            string[] userPasswordPair = userArray[i].Split(' ');


            //if username and password given match any user pair

            if (userPasswordPair[0] ==  newUsernameTextBox.Text)
            {
                successfulLogin = true;
                break;
            }

        }
        // if the username and password match a set in the file then successful login
        if (successfulLogin == true)
        {
            signErrorLabel.Text = "User Exists";

        }
        //if username and password did not match set
        else if (successfulLogin == false)
        {
            using (StreamWriter logfile = File.AppendText(userFilePath))
            {
                logfile.WriteLine(newUsernameTextBox.Text + " " + newPasswordTextBox.Text);
                logfile.Close();
            }
            Session["User"] = newUsernameTextBox.Text;
            Response.Redirect("TuitterDisplay.aspx");
        }
    }
}