We have reached the edge of the moon in our way to the truth, I’m not under the impact of alcoholic poisoning (I don’t drink at all), but I’m so happy to reach the last part of explaining or first expert advisor. Yes! This is the last part of the expert advisor lesson.



I hope you enjoyed the journey discovering how to write our simple yet important expert advisor.

Let’s take the final step.

Attached Files

Lesson16.pdf (40.3 KB, 2264 views)

__________________
Hope it helps !
Coders' Guru
Senior MQL programmer:
www.xpworx.com/custom.htm

Fantastic! Your work is invaluable!! Many many thanks!

i aggree with beer.your work souns greate.in my opinion it is MQL4 bible.thanks a lot

Codersguru,

You Da Man!
Thank you for posting and all your hard work.

You're welcome! I hope you've enjoyed the lessons.

__________________
Hope it helps !
Coders' Guru
Senior MQL programmer:
www.xpworx.com/custom.htm

Thanks for the great course. It is very useful.

How can I use a custom indicator like pricechannelstop in the EA?

Hi Guru,

Yep, excellent work, thanks for all this amazing help. It's going to take a few days to get to grips with all this but it's been really helpful to have your lessons.

Thanks again !

El Choco

Dear Sir

you have decleared the two static variables inside the block of the function. then every time start function recieves a quote it will call the crossed function,and every time when start calls crossed, crossed will first initilize the two varibles to zero,so how could you compare current_direction with last_direction?

int Crossed (double line1 , double line2)
{
static int last_direction = 0;
static int current_dirction = 0;

if(line1>line2)current_dirction = 1; //up
if(line1<line2)current_dirction = 2; //down



if(current_dirction != last_direction) //changed
{
last_direction = current_dirction;
return (last_direction);
}
else
{
return (0);
}
}

suffic369,

Thanks for the question!


There are two kinds of variables in MQL4, normal variables and static variables;
The static variables are very like the normal variables with only one extra feature:

The initialization of the static variables occurs only one time.
Which means if you write a line of code like that:


static int last_direction = 0;


You mean:

If this is the first call of the program, initialize the variable to 0, else (if it's the second, third, fourth etc call) don't initialize the variable again.


But if you used a normal variable instead of static variable, every time you call your program the initialization of the variable will be occurred.

__________________
Hope it helps !
Coders' Guru
Senior MQL programmer:
www.xpworx.com/custom.htm

Hi, at start i want say thank you for your great job you're doing to help us to learn programming MQL4.

I've got problem. My First EA is not working correct. When MA lines getting crossed, MT try to open order but such error occurs every time:

2006.04.19 13:14:12 My_First_EA EURUSD,M1: Error opening SELL order : 4109

It is the same with Long position.

#define ERR_TRADE_NOT_ALLOWED 4109

I know it is connect with these lines of code:

if(isCrossed == 2)
{

ticket=OrderSend(Symbol(),OP_SELL,Lots,Bid,3,0,Bid-TakeProfit*Point,"My EA",12345,0,Red);
if(ticket>0)
{
if(OrderSelect(ticket,SELECT_BY_TICKET,MODE_TRADES )) Print("SELL order opened : ",OrderOpenPrice());
}
else Print("Error opening SELL order : ",GetLastError());
return(0);
}
return(0);
}

But i can't get it why this error occurs. I would be pleased if you could help me. Best Wishes.