private void Login_Button_Click(object sender, EventArgs e) { MainClass mc = new MainClass(); mc.OpenConnection(); mc.AppLogin(UserNameTBox.Text, PasswordTBox.Text); try { if (MainClass.Flag == 1) { new SignIn().Show(); mc.CloseConnection(); MainClass.Flag = 0; this.Hide(); } else if (MainClass.Flag == 2) { new LoginChange().Show(); mc.CloseConnection(); MainClass.Flag = 0; this.Hide(); } else if (MainClass.Flag == 0) { mc.CloseConnection(); MessageBox.Show("Please Check Your Login Details !", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error); } } catch (Exception ex) { mc.CloseConnection(); MessageBox.Show(ex.Message); } }