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Taken from the dll manual.

VARIANT_BOOL Conectar( [in] BSTR IPAdd, [in] long Portl)

Should I DO it like this ?

DLL FUNCTION Conectar( IPAdd AS LPSTR, Portl AS LONG ) AS BOOL PASCAL LIB "xxxxxx.dll"

Thisis my code...

PUBLIC hDLL := LoadLibrary("xxxxxx.dll")
lReturn:=Conectar("192.168.1.1",9999)

MsgInfo( lReturn )

FreeLibrary( hDLL )


But I get a nil value, instead of .T. or .F.

What am I doing wrong... any help will be appreciated

Thanks in advance.

From Chile
Adolfo

UP...
Any idea?

Hi Adolfo, Regards,

George

George.. thanks for answering.

I can load the DLL with no problem, no error, I can see the number of the Handle with no problem.

I tried to call the function in this way.

DLL32 FUNCTION Connect_NET( IPAdd AS STRING, Portl AS LONG ) AS BOOL PASCAL FROM "Connect_NET" LIB "zkemsdk.dll"

DLL32 FUNCTION Connect_NET( IPAdd AS STRING, Portl AS LONG ) AS BOOL FROM "Connect_NET" LIB "zkemsdk.dll"

DLL32 FUNCTION Connect_NET( IPAdd AS LPSTR, Portl AS LONG ) AS BOOL PASCAL LIB "zkemsdk.dll"

DLL32 FUNCTION Connect_NET( IPAdd AS LPSTR, Portl AS LONG ) AS BOOL LIB "zkemsdk.dll"



All of them with the same result NIL, no .T. or .F. as supposed
DLL manual says the function name and paramteres are:

VARIANT_BOOL Connect_NET( [in] BSTR IPAdd, [in] long Portl)
Return True if connected, otherwise False.... but I get a NIL

I'm out of ideas.

Alfonso,

it is not the same a VARIANT_BOOL than a BOOL. There is no an automatic conversion from a VARIANT from the DLL call command, thats probably why you are geting nil as the return value

Antonio... thanks...

So how am I supposed to retrieve it.. as what ?

Thanks

Probably as a pointer to the variant (just a generic pointer)

But once you get such pointer, you need to properly inspect it. Harbour has some functions for OLE management that you may try to adapt.

Ok
reading some info about it.. I discovered that

VARIANT_BOOL has 2 possible values

VARIANT_FALSE = 0
VARIANT_TRUE = -1

So maybe the function returns 0 or -1
DLL32 has no "Unknown" return value to declare, Because that way I could inspect it, or not.

Adolfo,

Te hablo en español y abreviamos

Estoy revisando tu código y veo que se usa BSTR y eso no es un LPSTR. He buscado en el código de Harbour y efectivamente es una cadena "wide".

En Harbour\contrib\hbwin\olecore.c encuentras este código:
que basicamente convierte un item de Harbour (tipo cadena) a una cadena wide BSTR (que son las usadas en OLE).

Asi que lo primero de todo es convertir tu cadena en BSTR y luego proporcionarla a tu función.

Despues de revisarlo no estoy tan seguro de que sea eso lo que necesitas, pues esa función convierte de un item de OLE a cadena y no de un item de Harbour.

Aqui esta todo el código de olecore.c para revisarlo pues se usan BSTR en otras partes más y asi ver cual es la forma correcta de hacer la conversión:

https://github.com/harbour/core/blob/ma ... /olecore.c

Antonio...

Mirando algunas soluciones para mi problema, encontre esto




std::string ConvertWCSToMBS(const wchar_t* pstr, long wslen)
{
int len = ::WideCharToMultiByte(CP_ACP, 0, pstr, wslen, NULL, 0, NULL, NULL);

std::string dblstr(len, '\0');
len = ::WideCharToMultiByte(CP_ACP, 0 /* no flags */,
pstr, wslen /* not necessary NULL-terminated */,
&dblstr[0], len,
NULL, NULL /* no default char */);

return dblstr;
}

Y aqui de BSTR a STR, posibles 3
//----------------------
#include <comdef.h>

std::string myString = _bstr_t (myBSTR);



//----------------
void f(BSTR ms_str)
{
std::wstring ws(ms_str);
}

//*---------------

BSTR ConvertMBSToBSTR(const std::string& str)
{
int wslen = ::MultiByteToWideChar(CP_ACP, 0 /* no flags */,
str.data(), str.length(),
NULL, 0);

BSTR wsdata = ::SysAllocStringLen(NULL, wslen);
::MultiByteToWideChar(CP_ACP, 0 /* no flags */,
str.data(), str.length(),
wsdata, wslen);
return wsdata;
}

Que me dices.. no soy experto en C, pero este problema me tiene acogotado.

Saludos..

De ahi busco las opciones de recibir bien el VARIANT_BOOL

Adolfo,

Si la IP fuese 192.168.1.1 proporcionasela asi: Chr( 0 ) + "1" + Chr( 0 ) + "9" + Chr( 0 ) + "2" + Chr( 0 ) + "." + ...

Gracias Master...
Pruebo y comento...