Not really familiar with c + +, some dizzy,
Feeling is pData1 and pOut1 form right? But I don't know how to change, never understand pointer

The third party to provide the barcode. DLL files, def file is:

 
The LIBRARY barcode 
EXPORTS 
Encode @ 1 
Decode @ 2 

Now I'd like to call these two functions, but it is always a problem, UCHAR inside each other with a header file is unsigned char,

 
# include "PCH. H" 
#include  
#include  
# include "bar_cfg. H" 
# include "bar_def. H" 
# include "bar_err. H" 
# include "bar_type. H" 

# pragma comment (lib, "barcode. Lib") 
_declspec (dllimport) LONG decode (UCHAR * pData, UCHAR * pOut); 
_declspec (dllimport) LONG encode (UCHAR * pData, UCHAR * pOut); 

Int main () 
{
UCHAR pData1 [28]="12345678901234567890123456"; 
UCHAR pOut1 [400]=""; 
LONG rc=encode (pData1 pOut1); 

STD: : cout & lt; <"Encode \ n"; 
STD: : cout & lt; STD: : cout & lt; <"\ n"; 
STD: : cout & lt; STD: : cout & lt; <"\ n"; 
} 

Compile error message:

 
Severity code shows the project file line prohibits display status 
Error LNK2019 cannot resolve the external symbol "__declspec (dllimport) long __cdecl encode (unsigned char *, unsigned char *)" (__imp_? Encode @ @ YAJPAE0 @ Z), the symbol referenced in the function _main barcode_test C: \ documents \ Workspace \ ykzx - barcode \ barcode_test \ barcode_test \ barcode_test obj 1 
Error LNK2019 cannot resolve the external symbol "__declspec (dllimport) long __cdecl decode (unsigned char *, unsigned char *)" (__imp_? Decode @ @ YAJPAE0 @ Z), the symbol referenced in the function _main barcode_test C: \ documents \ Workspace \ ykzx - barcode \ barcode_test \ barcode_test \ barcode_test obj 1 

Dumpbin. Exe/exports barcode. DLL

 
The Dump of file barcode_test \ barcode_test \ barcode DLL 

The File Type: DLL 

Section contains the following exports for barcode. DLL 

Characteristics of 00000000 
FFFFFFFF time date stamp 
0.00 version 
1 the ordinal base 
2 number of functions provides 
2 the number of names 

The ordinal hint RVA name 

2 0 000018 d0 decode=_decode 
1 1 00001950 encode=_encode 

The Summary 

3000. The data 
1 d000. Rdata 
5000. Reloc 
1000. The RSRC 
76000. The text 

CodePudding user response:

Because you don't have to generate barcode. Lib
Command line perform:
Lib/def: def file name/out: output library file name/machine: corresponding 32/64 bit Intel x86 or x64 architecture

CodePudding user response:

reference 1/f, play big shoot early nuclear response:

because you don't have to generate barcode. The lib
Command line perform:
Lib/def: def file name/out: output library file name/machine: corresponding 32/64 bit Intel x86 or x64 architecture

This line not line?
# pragma comment (lib, "barcode. Lib")

CodePudding user response:

reference 1/f, play big shoot early nuclear response:

because you don't have to generate barcode. The lib
Command line perform:
Lib/def: def file name/out: output library file name/machine: corresponding 32/64 bit Intel x86 or x64 architecture

The other party provides barcode. Lib, has been in the source directory, and added to the project,

CodePudding user response:

Use lib command to generate the barcode. Lib, is still the same error,

CodePudding user response:

_declspec (dllimport) LONG __cdecl decode (UCHAR * pData, UCHAR * pOut);
_declspec (dllimport) LONG __cdecl encode (UCHAR * pData, UCHAR * pOut);

CodePudding user response:

reference 5 floor early play the play nuclear war response:

_declspec (dllimport) LONG __cdecl decode (UCHAR * pData, UCHAR * pOut);
_declspec (dllimport) LONG __cdecl encode (UCHAR * pData, UCHAR * pOut);

Is still the same error