Expert Advisor Programming by Andrew R. Young

Order Management
Note the condition (CurrentStop > MaxStopLoss || CurrentStop == 0). If there is no stop loss
placed with the order, then the condition CurrentStop > MaxStopLoss will never be true, because
MaxStopLoss will never be less than zero. Thus, we add an OR condition, CurrentStop == 0.
If the current order's stop loss is 0 (no stop loss), then as long as the remaining conditions are true,
the trailing stop will be placed.
Minimum Profit
Let's enhance our trailing stop by adding a minimum profit level. In the above example, the trailing
stop will kick in right away. If you set an initial stop loss of 100 pips, and your trailing stop is 50 pips,
the stop loss would be set to 50 pips immediately, invalidating your initial 100 pip stop loss.
Adding a minimum profit level will allow you to set an initial stop loss, while delaying the trailing stop
until a specified amount of profit is reached. In this example, let's assume an initial stop loss of 100
pips is set when the order is placed. We're using a trailing stop of 50 pips, with a minimum profit
level of 50 pips. When the profit for the order reaches 50 pips, the stop loss will be adjusted to break
even.
Let's add an external variable for our minimum profit setting:
extern int TrailingStop = 50;
extern int MinimumProfit = 50;
The following function modifies the stop loss for all buy market orders, checking the minimum profit
before doing so:
void BuyTrailingStop(string argSymbol, int argTrailingStop, int argMinProfit,
int argMagicNumber)
{
for(int Counter = 0; Counter