private void btnHangHoa_Click(object sender, EventArgs e)
{
Form form = searchOpenedForm("HangHoaManagerForm");
if (form == null)
{
form = new HangHoaManagerForm();
}
form.Show();
form.Activate();
}
private void hàngHóaToolStripMenuItem_Click(object sender, EventArgs e)
{
Form form = searchOpenedForm("HangHoaManagerForm");
if (form == null)
{
form = new HangHoaManagerForm();
}
form.MdiParent = this;
form.Show();
form.Activate();
}