private void btnAddPM_Click(object sender, EventArgs e)
{
FormAddDuLieuPhieuMuon f = new FormAddDuLieuPhieuMuon();
//f.d = new Form2.MyDel(this.Show);
f.ShowDialog();
}
private void btnAddPhieuMuon_Click(object sender, EventArgs e)
{
FormAddDuLieuPhieuMuon f = new FormAddDuLieuPhieuMuon(Username);
f.d = new FormAddDuLieuPhieuMuon.MyDel(this.ShowPM);
f.ShowDialog();
}