private void ProovedoresToolStripMenuItem_Click(object sender, EventArgs e)
{
WindowsFormsApp1.SupplierForm supplierForm = new WindowsFormsApp1.SupplierForm();
supplierForm.SetParent(this);
supplierForm.MdiParent = this;
supplierForm.Show();
}
public void SetParent(SupplierForm form)
{
refParent = form;
}