MarketPosition() 获取到的状态不对

onbar{
  ....
range{
   ....
    Print("开仓之前=" + Text(Date) + ",方向="+Text(MarketPosition())+", 合约=" + codePro.symbol + ", 当前持仓品种数=" + Text(symbolCount) +"最大持仓数=" + Text(MaxOpenSymbols));
    -------
    Print("开空之前时间=" + Text(Date) + ",方向="+Text(MarketPosition())+", 合约=" + codePro.symbol + ", 当前持仓品种数=" + Text(symbolCount) +"最大持仓数=" + Text(MaxOpenSymbols));
                tradeReturn=SellShort(Lots,Close);
                if(tradeReturn)
                {
                    if(MarketPosition() <> 0)
                    {
                        symbolCount = symbolCount + 1;
                    }
                    Print("[开空] 时间=" + Text(Date) + ",方向="+Text(MarketPosition())+", 合约=" + codePro.symbol + ", 当前持仓品种数=" + Text(symbolCount) +"最大持仓数=" + Text(MaxOpenSymbols));
                } Else
                {
                    Print("[开空] 失败 时间=" + Text(Date) + ",方向="+Text(MarketPosition())+", 合约=" + codePro.symbol + ", 当前持仓品种数=" + Text(symbolCount) +"最大持仓数=" + Text(MaxOpenSymbols));
                }