private void saveButton_Click(object sender, EventArgs e) { Course aCourse = new Course(); aCourse.Code = codeTextBox.Text; aCourse.Name = nameTextBox.Text; aCourse.Credit = (float)Convert.ToDouble(creditTextBox.Text); CourseBll aCourseBll = new CourseBll(); string msg = aCourseBll.SaveIntoDataBase(aCourse); MessageBox.Show(msg); }