能否实现 开平只播放一次声音的效果

Global BOOL SHiFuBuoFanSHenYen(False); If(MarketPosition != 1 AND JiongXian[1] >= JiongXian[ GuoLu] And Close[1] >= JiongXian[1]) { Buy(SHouSHu*100,Open); If(SHiFuBuoFanSHenYen == False) { PlayWavSound(\"D:\\\\c.wav\"); SHiFuBuoFanSHenYen = True; } } Else if(MarketPosition == 1 AND JiongXian[1] < JiongXian[ GuoLu] And Close[1] < JiongXian[1]) { Sell(0,Open); If(SHiFuBuoFanSHenYen == True) { PlayWavSound(\"D:\\\\a.wav\"); SHiFuBuoFanSHenYen = False; }