void mAveCost_Click(object sender, EventArgs e) { frmSingleInputBox fsAvecost = new frmSingleInputBox("Enter the new average cost...", ref sEngine); fsAvecost.ShowDialog(); if (fsAvecost.Response != "$NONE") { sEngine.EditAverageCostOfItem(sBarcode, sShopCode, fsAvecost.Response); ShowStatsAboutProduct(); } }