private void btn_changePassword(object sender, RoutedEventArgs e) { string oldPassword = OldPassword.Password; string newPassword = NewPassword.Password; string confirmPassword = ConfirmPassword.Password; var teacherBll = new TeacherBll(); if (!newPassword.Equals(confirmPassword)) { MessageBox.Show("Passwords donot match."); } else if (teacherBll.ChangePassword(oldPassword, newPassword)) { MessageBox.Show("Password Changed."); this.Close(); } else { MessageBox.Show("Wrong Old Password."); } }