private void panel3_Click(object sender, EventArgs e)
{
this.Hide();
BangGia frm = new BangGia();
frm.ShowDialog();
//WHEN SHOWDIALOG() END
frm.Dispose();
this.Show();
}
private void quànLýTàiKhoảnToolStripMenuItem_Click(object sender, EventArgs e)
{
BangGia bg = new BangGia();
bg.Show();
}