The code is below:
private double GetProfitRange(StrategyBase strategy, DateTime begin, DateTime end) {
double profit = 0.0;
this.Print("AllTrades : " + strategy.SystemPerformance.AllTrades.Count); // Always return zero.
List<Trade> rangeTrades = strategy.SystemPerformance.AllTrades.Where(t =>(t.Exit.Time > begin && t.Exit.Time < end)).ToList<Trade>();
foreach (Trade trade in rangeTrades) {
profit += trade.ProfitCurrency;
}
return profit;
}

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