private void btnRegisterClient_Click(object sender, RoutedEventArgs e)
{
if (cbStudent.SelectedItem != null && cbLecture.SelectedItem != null)
{
ClientLecture cl = new ClientLecture();
cl.Client = (Client)cbStudent.SelectedItem;
cl.Lecture = (Lecture)cbLecture.SelectedItem;
IQueryable <ClientLecture> duplicateCL = from dcl in dataContext.ClientLectures where dcl.Client == cl.Client where dcl.Lecture == cl.Lecture select dcl;
if (duplicateCL.Count() == 0)
{
dataContext.ClientLectures.InsertOnSubmit(cl);
dataContext.SubmitChanges();
RefreshTable();
}
else
{
MessageBox.Show("Student is already registered in that lecture.");
}
}
else
{
MessageBox.Show("Please select a student and a lecture to register.");
}
}
private void btnUnregisterClient_Click(object sender, RoutedEventArgs e)
{
if (cbStudent.SelectedItem != null && cbLecture.SelectedItem != null)
{
try
{
ClientLecture cl = (from cL in dataContext.ClientLectures where cL.ClientId == (int)cbStudent.SelectedValue where cL.LectureId == (int)cbLecture.SelectedValue select cL).First();
dataContext.ClientLectures.DeleteOnSubmit(cl);
dataContext.SubmitChanges();
RefreshTable();
}
catch
{
MessageBox.Show("Student not found in that lecture.");
}
}
else
{
MessageBox.Show("Please select a student and a lecture to unregister.");
}
}
