Expert Advisor Programming by Andrew R. Young

EXPERT ADVISOR PROGRAMMING
OrderSelect(CloseTicket,SELECT_BY_TICKET);
if(OrderCloseTime() == 0 && OrderType() == OP_BUYSTOP)
{
bool Deleted = OrderDelete(CloseTicket,Red);
}
As we did with the OrderClose() function above, we need to check the order type to be sure it is a
pending order. The pending order type constants are OP_BUYSTOP, OP_SELLSTOP, OP_BUYLIMIT and
OP_SELLLIMIT. To close other types of pending orders, simply change the order type.
If the order has been filled, then it is now a market order, and must be closed using OrderClose()
instead.
A Simple Expert Advisor
Let's see how the code we've discussed so far would work in an expert advisor. This is a simple
moving average cross system. A buy order is opened when the 10 period moving average is greater
than the 20 period moving average. When the 10 period moving average is less than the 20 period
moving average, a sell order is opened.
This EA will alternate between opening buy and sell orders. Orders will be closed when an order is
opened in the opposite direction, or by stop loss or take profit. We will use the global variables
BuyTicket and SellTicket to store the last order ticket. When a new order is opened, the last
order ticket is cleared. This prevents multiple consecutive orders from opening.
#property copyright "Andrew Young"
// External variables
extern double LotSize = 0.1;
extern double StopLoss = 50;
extern double TakeProfit = 100;
extern int Slippage = 5;
extern int MagicNumber = 123;
extern int FastMAPeriod = 10;
extern int SlowMAPeriod = 20;
// Global variables
int BuyTicket;
int SellTicket;
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