private void btnIn_Click(object sender, EventArgs e)
{
ds = hh.dsCuaHang;
InCuaHang f = new InCuaHang();
f.ShowDialog();
}
private void btnInTimKiem_Click(object sender, EventArgs e)
{
ds = hh.Tim(txtTenHang.Text);
InCuaHang f = new InCuaHang();
f.ShowDialog();
}