public StudentViewModel(Student student)
{
if (student == null)
{
throw new ArgumentNullException("student");
}
_student = student;
}
public void SaveStudent(Student student)
{
// If current student is a new record, it means this student is a new tuple, so we
// need to add it into table
if (student.IsNew)
{
AddStudent(student);
}
else
{
// Otherwise, the student may have existed, we need to find it and update its values to current values
// Here, we use LINQ to search the student.
var target = Students.AsEnumerable().FirstOrDefault(p => p.Field<Guid>(Student.StudentIDPropertyName) == student.StudentID);
if (target != null) // We indeed found our wanted student record, so update it
{
target.SetField<string>(Student.NamePropertyName, student.Name);
target.SetField<int>(Student.AgePropertyName, student.Age);
target.SetField<Gender>(Student.GenderPropertyName, student.Gender);
target.SetField<string>(Student.DescriptionPropertyName, student.Description);
}
}
_data.AcceptChanges();
this.Save();
}
/// <summary>
/// Adds one student as a new row to Students table
/// </summary>
/// <param name="student"></param>
private void AddStudent(Student student)
{
Students.Rows.Add(new object[]
{
student.StudentID,
student.Name,
student.Age,
student.Gender,
student.Description
});
}
public StudentViewModel()
{
Student newStudent = Student.CreateNewStudent(string.Empty, 18, Gender.Male, string.Empty);
_student = newStudent;
}