private void btnThemSPMoi_Click(object sender, EventArgs e)
        {
            this.Close();
            FormSanPham sp = new FormSanPham();

            sp.Show();
        }
 private void btnThemSPMoi_Click(object sender, EventArgs e)
 {
     this.Close();
     FormSanPham sp = new FormSanPham();
     sp.Show();
 }
        private void quảnLýSảnPhẩmToolStripMenuItem_Click(object sender, EventArgs e)
        {
            FormSanPham fsp = new FormSanPham();

            fsp.Show();
        }
 private void quảnLýSảnPhẩmToolStripMenuItem_Click(object sender, EventArgs e)
 {
     FormSanPham fsp = new FormSanPham();
     fsp.Show();
 }