单向双向：某些产品的手续费只在开仓时收取，有些则在开仓和平仓时都收取； The Gives that look In this particular table are from partnerships from which Investopedia receives payment. This payment may well effect how and wherever listings show up. Investopedia will not involve all provides offered inside the marketplace. This process calculates the worth of a trade based on The existing waiting for link from Social Network Posts (72)