Create your own MetaTrader extension (dll) - Page 6

Mistigri · #51 (**permalink**) 04-27-2009, 04:12 PM

Quote:

Originally Posted by fedecosta

Hello guys!

I have a problem trying to use this library.

I put them in metatrader\experts\library
I correctly define the path for the .def file

... but my EA print on the register this error: -65495

What can be the problem?
And, most, how to solve it?

Is it possible that the .def file can be corrupted?

Thanks in advance...

Hi Fedecosta,

Try to copy the def file directly under your c:\ drive ... That seems to work for me.
Note that this has nothing to do with DLL programming, it's specific to this EA...

Patrick

chiwing · #52 (**permalink**) 05-02-2009, 09:47 AM

Quote:

Originally Posted by Mistigri

Hi Tim,

When using dev-c++ the def file is generated for you automatically the problem is that you end up with function names that look like this :

PHP Code:


			
EXPORTS

    _Z11GetSMAArrayP8RateInfoiiPd@16 @ 1

    _Z12GetHighValueP8RateInfoii = _Z12GetHighValueP8RateInfoii@12 @ 2

    _Z12GetHighValueP8RateInfoii@12 @ 3

    _Z13GetCloseValueP8RateInfoii = _Z13GetCloseValueP8RateInfoii@12 @ 4

    _Z13GetCloseValueP8RateInfoii@12 @ 5

    _Z11GetSMAArrayP8RateInfoiiPd = _Z11GetSMAArrayP8RateInfoiiPd@16 @ 6

Now you need to make sure you add the following check around your code

PHP Code:


			
#ifdef __cplusplus

extern "C" {

#endif





#ifdef __cplusplus

}

#endif

Attached are the sample files I did for VS2008 but this time using dev-c++ ...
Hope this helps

do u mean that when write dll file,
the function in the def file should add _z12 at the begin?

that means in .mq4 file
call finction: get_max_deviation

then in .def file
the transfered function : _z12get_max_deviation???

what means for the @ number after the function name

thanks

chiwing · #53 (**permalink**) 05-02-2009, 12:57 PM

Quote:

Originally Posted by Mistigri

Attached are the sample files I did for VS2008 but this time using dev-c++ ...
Hope this helps

Attached Files
MistigriFX Sample Debug.mq4 (2.1 KB, 15 views)
MSFXDEV.zip (8.6 KB, 17 views )

I have dl your files , and compile the .cpp by the picture show
but occur error

do my compile method wrong , how do i compile it to dll ? (i am a c++ beginner ^^)

veematics · #54 (**permalink**) 05-08-2009, 04:26 AM

Hello All and Mistigri,
i would like to know how to create shared function so that i don't have to copy-paste the functions on each DLL...

it's equals method if i use mqh (libraries)...but in DLL format

I use Visual Studio as well

veematics · #55 (**permalink**) 05-12-2009, 06:20 AM

I just notice that the DLL i made is a shared MFC, that is why it return error(126) in other computer while there's no problem with my computer.

I would like to know on how to convert shared MFC to static linked ?
because when i set it to static it display error like this:
error LNK2019: unresolved external symbol ...

wolfe · #56 (**permalink**) 05-12-2009, 08:25 AM

Quote:

Originally Posted by veematics

I just notice that the DLL i made is a shared MFC, that is why it return error(126) in other computer while there's no problem with my computer.

I would like to know on how to convert shared MFC to static linked ?
because when i set it to static it display error like this:
error LNK2019: unresolved external symbol ...

Make sure on other computer, you load the compiled release version, and not the debug version.

veematics · #57 (**permalink**) 06-10-2009, 05:28 AM

Hello, i create a dll that write a file to specific directory with fprintf function, the bug happen when i run mt4 from desktop's shortcut .. it crashed the mt4, but if i run mt4 directly from windows explorer everything works perfectly.

Any idea how to solve this problem... needs help !

veematics · #58 (**permalink**) 06-16-2009, 07:29 AM

wolfe.. could you show me how to release compiled version.. not debug version ?? .. i'm on visual studio

Bobtrade · #59 (**permalink**) 06-21-2009, 01:10 PM

Hi ,

This is my first post ever on this forum. Hope I'm doing it the right way.

Just want to say Thank You for explaining about DLL 's.
I can handle basic mql4 but know nothing about dll development.

So, tnx again and I'l be back

cheers,

wolfe · #60 (**permalink**) 06-21-2009, 06:52 PM

Quote:

Originally Posted by veematics

wolfe.. could you show me how to release compiled version.. not debug version ?? .. i'm on visual studio

I'm using VS2008 Express. There should be a tab at the top of your VS compiler that allows you to select between debug and release. Select release and compile. The compiler will give you a file path where your release dll is stored. Follow the file path, and copy the dll to C:\WINDOWS\system32.

That should work.