Expert Advisor Programming by Andrew R. Young

EXPERT ADVISOR PROGRAMMING
bool VerifyUpperStopLevel(string argSymbol, double argVerifyPrice,
double argOpenPrice = 0)
{
double StopLevel = MarketInfo(argSymbol,MODE_STOPLEVEL) * Point;
if(argOpenPrice == 0) double OpenPrice = MarketInfo(argSymbol,MODE_ASK);
else OpenPrice = argOpenPrice;
double UpperStopLevel = OpenPrice + StopLevel;
if(argVerifyPrice > UpperStopLevel) bool StopVerify = true;
else StopVerify = false;
}
return(StopVerify);
We pass the currency symbol, the price to verify, and the order opening price (optional) as
arguments. By default, the stop level is calculated relative to the Ask price. If argOpenPrice is
specified, the stop level will be calculated relative to that price instead. (Use this when verifying stop
loss and take profit prices for pending orders).
The function will check to see whether argVerifyPrice is greater than the UpperStopLevel. If it is,
the return value will be true. Otherwise, false. You can use this function to check for a valid stop loss,
take profit or pending order price, without modifying the original price. Here's an example where we
check a stop loss price and show an error message if the price is not valid:
bool Verified = VerifyUpperStopLevel(Symbol(),SellStopLoss);
if(Verified == false) Alert("Sell stop loss is invalid!");
The code to check the stop level below the current or pending price is in Appendix D. Our second set
of functions is similar, except that they will automatically adjust the invalid stop loss, take profit or
pending order price to a valid one:
double AdjustAboveStopLevel(string argSymbol, double argAdjustPrice, int argAddPips = 0,
double argOpenPrice = 0)
{
double StopLevel = MarketInfo(argSymbol,MODE_STOPLEVEL) * Point;
if(argOpenPrice == 0) double OpenPrice = MarketInfo(argSymbol,MODE_ASK);
else OpenPrice = argOpenPrice;
double UpperStopLevel = OpenPrice + StopLevel;
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