private void ShowEditFrm()
        {
            if (dgv.CurrentRow == null)
            {
                return;
            }

            AddEditSubjectFrm frm = new AddEditSubjectFrm();
            frm.Parent = this.MdiParent;
            frm.EditMode = true;
            frm.SubjectID = (string)dgv.CurrentRow.Cells[0].Value.ToString();
            frm.ShowDialog();
            LoadSubjectToDGV("SELECT * FROM subject");
        }
 private void ShowAddFrm()
 {
     AddEditSubjectFrm frm = new AddEditSubjectFrm();
     frm.Parent = this.MdiParent;
     frm.ShowDialog();
     LoadSubjectToDGV("SELECT * FROM subject");
 }