private void nxt_btn_Click(object sender, EventArgs e) { if (int.TryParse(password_txtbx.Text, out psw)) { psw = int.Parse(password_txtbx.Text); user_class clss = new user_class(); clss.Name = User_txtbx.Text; clss.Password = psw; nme = clss.Name; pass = clss.Password; } else { MessageBox.Show("Please input a correct Password(number)"); } try { log_now = 1; login = DateTime.Now; loginn = login.ToString(); MySqlConnection connection = new MySqlConnection("datasource=localhost;port=3306;username=root;password=jmsb;server=127.0.0.2;database=internal_communication_4;persistsecurityinfo=True"); string query1 = "SELECT user_name, user_password, user_position FROM internal_communication_4.user WHERE (user_name LIKE '" + this.nme + "' AND user_password = '******');"; connection.Open(); // dbhellper db = new dbhellper(); // db.connexionopen("open", query1); MySqlCommand command = new MySqlCommand(query1, connection); MySqlDataReader MyReader2; MyReader2 = command.ExecuteReader(); while (MyReader2.Read()) { if (MyReader2.GetString(0) != null) { okay = true; } } if (okay == true) { user_name = nme; user_position = MyReader2["user_position"].ToString(); project_selection_form frm = new project_selection_form(); frm.Show(); this.Hide(); connection.Close(); Random rnd = new Random(); int logid = rnd.Next(1, 100000); logs_class log = new logs_class(); log.ID = logid; log.Log_current = log_now; log.Log_in = loginn; connection.Open(); //how to insert foreign key values string query3 = "INSERT INTO internal_communication_4.logs(log_id,log_in,user_user_id,log_current) VALUES( @log_id, @log_in, (SELECT user_id FROM internal_communication_4.user WHERE (user_name LIKE '" + this.nme + "' AND user_password = '******')), @log_current)"; MySqlCommand comm = connection.CreateCommand(); comm.CommandText = query3; comm.Parameters.AddWithValue("@log_id", log.ID); comm.Parameters.AddWithValue("@log_in", log.Log_in); comm.Parameters.AddWithValue("@log_current", log.Log_current); comm.ExecuteNonQuery(); connection.Close(); } else { MessageBox.Show("Wrong password or/and username"); } } catch { MessageBox.Show("source code error"); } }