// add button event handler
private void addButton_Click(object sender, EventArgs e)
{
string badFieldName = null; // variable for bad field name
string adviceString = null; // variable for advice string
if (!haveValidFirstName)
{
badFieldName = "First Name";
adviceString = "Enter First Name";
}
else if (!haveValidLastName)
{
badFieldName = "Last Name";
adviceString = "Enter Last Name";
}
else if (!haveValidAcademicDepartment)
{
badFieldName = "Department";
adviceString = "Enter Department";
}
else if (!haveValidEmailAddress)
{
badFieldName = "Email Address";
adviceString = "Enter Email Address";
}
else if (!haveValidSnailMailAddress)
{
badFieldName = "Mail Address";
adviceString = "Enter Mailing Address";
}
else if (!haveValidGraduationYear)
{
badFieldName = "Graduation Year";
adviceString = "Enter Graduation Year";
}
if (badFieldName != null)
{
MessageBox.Show($"Invalid {badFieldName}.\n{adviceString}", "Data Entry Error");
return;
}
// assign student contact object
StudentContact = new StudentContact(emailAddressTextBox.Text.Trim(),
snailMailAddressTextBox.Text.Trim());
DialogResult = DialogResult.OK;
}
// constructor using from file string to create a new student
public Student(string fromFile) : base(fromFile)
{
char[] delimiters = { '|', ',' };
string[] tokens = fromFile.Split(delimiters, StringSplitOptions.RemoveEmptyEntries);
contact = new StudentContact(tokens[4], tokens[5]);
graduationYear = int.Parse(tokens[6]);
if (tokens.Length > 6)
{
for (int i = 7; i < tokens.Length; i++)
{
CourseList.Add(tokens[i]);
}
}
}
//private List<string> courseList;
// constructors
public Student(string fname, string lname, string department, StudentContact contact, string type, int year, List <string> courses) :
base(fname, lname, department, type)
{
this.contact = (!StudentContact.isNull(contact)) ? contact :
throw new ArgumentException("Null value is unaccepted");
graduationYear = (isValidGraduationYear(year)) ? year :
throw new ArgumentException("Graduation year is invalided");
if (courses == null)
{
courses = new List <string> {
" "
};
}
else
{
CourseList = courses;
}
}
// function to check is an object is null
public static bool isNull(StudentContact contact)
{
return((contact == null) ? true : false);
}