SqlConnection connection = new SqlConnection(@"Data Source = SQL2016.fse.network;Initial Catalog=db_1620708_webuser;Persist Security Info=True; User ID =user_db_1620708_webuser; Password=Chester1991");
            connection.Open();
            SqlCommand cmd = new SqlCommand("select count (*) from webusers where Username ='" + TextUsername + "' and Password = '" + txtPassword + "'");
            cmd.Connection = connection;
            int M = Convert.ToInt32(cmd.ExecuteScalar());
            if (M > 0)
            {
                Response.Redirect("Default.aspx");
            }
            else
            {
                lBLInvalid.Visible = true;
                lBLInvalid.Text = "Invalid Username and Password";
                connection.Close();