private void addToolStripMenuItem_Click(object sender, EventArgs e)
        {
            ProductsSheetForm form = new ProductsSheetForm();

            form.ShowDialog();
            refreshDataGrid();
        }
 private void editToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (dataGridSheets.SelectedRows.Count > 0)
     {
         ProductsSheetForm form = new ProductsSheetForm(list[dataGridSheets.SelectedRows[0].Index]);
         form.ShowDialog();
         refreshDataGrid();
     }
 }