private void UpdateGroupsListHandler(object sender, EventArgs e)
{
listBoxGroups.Items.Clear();
listBoxStudents.Items.Clear();
listBoxMarks.Items.Clear();
groupsIndices.Clear();
groupDataTable?.Dispose();
groupDataTable = college.GetGroupsByGroupTypeId(
groupTypesDataTable[comboBoxParting.SelectedIndex].group_type_id);
for (int i = 0; i < groupDataTable.Rows.Count; i++)
{
listBoxGroups.Items.Add(groupDataTable[i].group_name);
groupsIndices.Add(groupDataTable[i].group_id);
}
}
