DefineDLLFunc C++ Example

March 29th, 2023, 10:09 PM

Hi, I'm trying to create a HelloWorld example c++ project but am getting this error from TS when calling it: "Invalid number of parameters were passed to a user dll function".
I'm not a c++ programmer but a C# programmer creating a wrapper for C# COM.

Here's the code:

------------------------------------------------------------------
The c++ code:
-----------------------------------------------------------------
COMTestingInterop.h:
// COMTESTINGINTEROP.h - Contains declarations of functions
#pragma once

#ifdef COMTESTINGINTEROP_EXPORTS
#define COMTESTINGINTEROP_API __declspec(dllexport)
#else
#define COMTESTINGINTEROP_API __declspec(dllimport)
#endif

extern "C" COMTESTINGINTEROP_API LPSTR hello(LPSTR world);
------------------------------------------------------------------------
ComTestingInterop.cpp:
#include "pch.h"
#include "COMTestingInterop.h"

LPSTR hello(char* world)
{
return LPSTR(world);
}
----------------------------------------------------------------------------------

EasyLanguage:
DefineDLLFunc: "COMTestingInterop.dll",LPSTR,"hello",LPSTR; {World} ;

Vars:
World( "Hey from TS" ) ;

once clearprintlog;
print(hello(World));

--------------------------------------------------------------------------------
If I remove the arguments, and return from the cpp function:
return LPSTR("hello from cpp");
It gets passed back to TS and prints to the log fine. The issue seems to be isolated to being able to add and pass arguments.

April 9th, 2023, 10:04 PM

Hello TheMetalDog,

First, let me say I am making a suggestion without trying. Sorry, but I'm on the road and don't have access to a computer with a compiler.

The signature of your function does not exactly match. LPSTR is Microsoft's "long pointer to a unicode string" if I remember correctly. The "char *" is a pointer to a character. Not identical in the C/C++ domain.

LPSTR hello(LPSTR world)
{
return LPSTR(world);
}

Try that and let me know if it works. Good luck!

DefineDLLFunc C++ Example

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DefineDLLFunc C++ Example