public bool Validate () { AmountAdded = TF2Value.Zero; List<string> errors = new List<string> (); foreach (TradeUserAssets asset in Trade.OtherOfferedItems) { var item = Trade.OtherInventory.GetItem(asset.assetid); if (item.Defindex == 5000) AmountAdded += TF2Value.Scrap; else if (item.Defindex == 5001) AmountAdded += TF2Value.Reclaimed; else if (item.Defindex == 5002) AmountAdded += TF2Value.Refined; else { var schemaItem = Trade.CurrentSchema.GetItem (item.Defindex); errors.Add ("Item " + schemaItem.Name + " is not a metal."); } } if (AmountAdded == TF2Value.Zero) { errors.Add ("You must put up at least 1 scrap."); } // send the errors if (errors.Count != 0) SendTradeMessage("There were errors in your trade: "); foreach (string error in errors) { SendTradeMessage(error); } return errors.Count == 0; }