If a trade is closed by Stop loss, the volume is doubled; if it’s closed by Take profit the minimum volume is used. OnTradeTransaction is used to determine whether a trade was performed after the activation of Stop loss or Take profit.
The excellent enumeration ENUM_DEAL_REASON was added in build 1625:
ENUM_DEAL_REASON | Reason description |
---|---|
… | … |
DEAL_REASON_SL | The operation was executed as a result of Stop Loss activation |
DEAL_REASON_TP | The operation was executed as a result of Take Profit activation |
… | … |
It can be checked in OnTradeTransaction.
In other words, it is a very simple and reliable way to determine that a trade resulted from Take Profit or Stop Loss.
At the moment (build 1626), this Expert Advisor can only be checked in a live test – by launching it on a chart or in a debug mode on real data (F5 in the MetaEditor editor). I used the following bypass maneuver:
In OnTradeTransaction, we determined whether Take Profit or Stop Loss triggered:
      if(deal_symbol==m_symbol.Name() && deal_magic==m_magic)         if(deal_entry==DEAL_ENTRY_OUT)           {             if(deal_reason==DEAL_REASON_SL)               ExtLot*=2.0;             else if(deal_reason==DEAL_REASON_TP)               ExtLot=m_symbol.LotsMin();           }