public static void DeleteSubject(string subjectName)
{
/*
* Deletes the specified subject and groups
* with that subject, and those groups linked with staff.
*/
int subjectId = GetSubjectIdByName(subjectName);
SqlCommand comm = new SqlCommand("SELECT GroupId FROM Groups WHERE SubjectId = @SubjectId");
comm.Parameters.AddWithValue("@SubjectId", subjectId);
DataTable dt = SqlTools.GetTable(comm);
SqlCommand deleteCommand = new SqlCommand();
SqlParameter groupId = new SqlParameter("@GroupId", "");
deleteCommand.Parameters.Add(groupId);
for (int i = 0; i < dt.Rows.Count; i++)
{
deleteCommand.CommandText = "DELETE FROM StaffGroupsLink WHERE GroupId = @GroupId";
groupId.Value = (int)dt.Rows[i]["GroupId"];
SqlTools.ExecuteNonQuery(deleteCommand);
}
comm.CommandText = "DELETE FROM Groups WHERE SubjectId = @SubjectId";
SqlTools.ExecuteNonQuery(comm);
comm.CommandText = "DELETE FROM Subjects WHERE SubjectName = @SubjectName";
comm.Parameters.AddWithValue("@SubjectName", subjectName);
SqlTools.ExecuteNonQuery(comm);
AdminForm.RefreshLists();
}
public static void AddNewSubject(string subjectName)
{
/*
* Adds a new subject to the table.
*/
SqlCommand comm = new SqlCommand("INSERT INTO Subjects (SubjectName) VALUES (@SubjectName)");
comm.Parameters.AddWithValue("@SubjectName", subjectName);
SqlTools.ExecuteNonQuery(comm);
AdminForm.RefreshLists();
}
public static void DeleteStudent(string studentName)
{
/*
* Deletes the student with the specified student name
* from the students table and any links to it.
*/
int studentId = GetStudentTableId(studentName);
SqlCommand comm = new SqlCommand("DELETE FROM Students WHERE StudentId = @StudentId");
comm.Parameters.AddWithValue("@StudentId", studentId);
SqlTools.ExecuteNonQuery(comm);
AdminForm.RefreshLists();
}
public static void DeleteStaffMember(string staffName)
{
/*
* Delete staff member by specified staff name,
* and group links with that staff member in.
*/
int staffId = Staff.GetStaffIdByName(staffName);
SqlCommand comm = new SqlCommand("DELETE FROM StaffGroupsLink WHERE StaffId = @StaffId");
comm.Parameters.AddWithValue("@StaffId", staffId);
SqlTools.ExecuteNonQuery(comm);
comm.CommandText = "DELETE FROM Staff WHERE StaffName = @StaffName";
comm.Parameters.AddWithValue("@StaffName", staffName);
SqlTools.ExecuteNonQuery(comm);
// Repopulate list.
AdminForm.RefreshLists();
}
public static void DeleteGroup(string groupName)
{
/*
* DeleteGroup deletes the given group from
* the database.
*
* Arguments:
* groupName (string): The name of the group to delete.
*/
int groupId = GetGroupIdByName(groupName);
// Delete all references to Group in StaffGroupsLink
SqlCommand comm = new SqlCommand("DELETE FROM StaffGroupsLink WHERE GroupId = @GroupId");
comm.Parameters.AddWithValue("@GroupId", groupId);
SqlTools.ExecuteNonQuery(comm);
// Delete from Groups table
comm.CommandText = "DELETE FROM Groups WHERE GroupId = @GroupId";
SqlTools.ExecuteNonQuery(comm);
// Repopulate the list to view affected groups.
AdminForm.RefreshLists();
}
private void SaveGroupButton_Click(object sender, EventArgs e)
{
/*
* SaveButton executes the SQL query needed for inserting
* a new Group and its related staff members.
* newGroup defines whether a group is being edited or
* a new group is being created.
*/
if (!newGroup)
{
// Delete all cases of the group beforehand to avoid conflicts.
SqlCommand comm = new SqlCommand("DELETE FROM StaffGroupsLink WHERE GroupId = @GroupId");
comm.Parameters.AddWithValue("@GroupId", groupId);
SqlTools.ExecuteNonQuery(comm);
SqlParameter staffId = new SqlParameter("@StaffId", "");
// Insert the new group-staff links with the selected staff
comm.CommandText = "INSERT INTO StaffGroupsLink (GroupId, StaffId) VALUES (@GroupId, @StaffId)";
comm.Parameters.Add(staffId);
foreach (string o in staffList)
{
// Loop over each Staff ID in the list.
staffId.Value = Staff.GetStaffIdByName(o);
SqlTools.ExecuteNonQuery(comm);
}
// Update with the new subject if changed
comm.CommandText = "UPDATE Groups SET SubjectId = @SubjectId WHERE GroupId = @GroupId";
comm.Parameters.AddWithValue("@SubjectId", Subjects.GetSubjectIdByName(subjectsComboBox.SelectedItem.ToString()));
SqlTools.ExecuteNonQuery(comm);
// Update with the new Academic Year if changed
comm.CommandText = "UPDATE Groups SET AcademicYearId = @AcademicYearId WHERE GroupId = @GroupId";
comm.Parameters.AddWithValue("@AcademicYearId", Groups.GetYearIdByName(academicYearComboBox.SelectedItem.ToString()));
SqlTools.ExecuteNonQuery(comm);
// Repopulate the list with the new group.
AdminForm.RefreshLists();
Close();
}
else
{
// New group
if (groupNameTextBox.Text != "" && academicYearComboBox.SelectedIndex != -1 && subjectsComboBox.SelectedIndex != -1 && lecturerBox.Items.Count != 0)
{
// Insert the parameters into the query.
SqlCommand comm = new SqlCommand("INSERT INTO Groups (GroupName, SubjectId, AcademicYearId) VALUES (@GroupName, @SubjectId, @AcademicYearId)");
comm.Parameters.AddWithValue("@GroupName", groupNameTextBox.Text);
comm.Parameters.AddWithValue("@SubjectId", Subjects.GetSubjectIdByName(subjectsComboBox.SelectedItem.ToString()));
comm.Parameters.AddWithValue("@AcademicYearId", Groups.GetYearIdByName(academicYearComboBox.SelectedItem.ToString()));
SqlTools.ExecuteNonQuery(comm);
SqlParameter StaffId = new SqlParameter("@StaffId", "");
comm.Parameters.Add(StaffId);
// Get the newly created group ID
comm.Parameters.AddWithValue("@GroupId", Groups.GetGroupIdByName(groupNameTextBox.Text));
comm.CommandText = "INSERT INTO StaffGroupsLink (GroupId, StaffId) VALUES (@GroupId, @StaffId)";
foreach (string o in lecturerBox.Items)
{
// Loop through the staff ID's and add them
StaffId.Value = Staff.GetStaffIdByName(o);
SqlTools.ExecuteNonQuery(comm);
}
AdminForm.RefreshLists();
Close();
}
}
}