Question

我知道我的问题，答案存在于网站的任何地方，但是，我有更多。

我有zip库并在另一个C ++项目中使用它。

Zip库：的 czip.h

#ifndef _CZIP_H_
#define _CZIP_H_

#include <fcntl.h>
#include <io.h>
#include <stdlib.h>
#include <windows.h>
#include <sys\stat.h>

#include <stdio.h>


#ifndef DLL_INTERNAL
#define DLL_INTERNAL __declspec( dllimport )
#endif 

class DLL_INTERNAL CZipException
{
public:
CZipException( const char*fm, ... );
const char* GetString() { return m_sMessage; }
protected:
char m_sMessage[ 128 ];
};


// pure virtual
class DLL_INTERNAL CMamaZip
{
public:
CMamaZip( const char *sSourceFileName );
void SwapSize( const char *sTargetFileName );
protected:
virtual int HardWork( int inFile, int outFile ) = 0;

char m_sSourceFileName[ MAX_PATH ];
char *m_sOperation;
};


class DLL_INTERNAL CZip : public CMamaZip
{
 public:
CZip( const char *sSourceFileName );
 protected:
virtual int HardWork( int inFile, int outFile );
};


class DLL_INTERNAL CUnzip : public CMamaZip
{
 public:
CUnzip( const char *sSourceFileName );
 protected:
virtual int HardWork( int inFile, int outFile );
};

#endif // _CZIP_H_

czip.cpp：

#define DLL_INTERNAL __declspec( dllexport )
#include "czip.h"
#include "tailor.h"


// global variables instancied in gzip 
extern "C" {

extern int dozip( int, int);
extern int dounzip( int, int );
extern long time_stamp;
extern char ifname[MAX_PATH_LEN]; 
extern int save_orig_name;

extern int ifd;
extern int ofd;

} 

int inFile, outFile;

// this function is called by gzip when there is an error
// instead of doing an exit( .. )
extern "C" void do_exit_dll(int exitcode)
{
close( inFile );
close( outFile );
throw( CZipException( "problem with zipping/unzipping operation : %d", exitcode ) );    
}  



CZipException::CZipException( const char* fm, ... )
{
char *p = m_sMessage;
va_list args;
va_start( args, fm );
p += vsprintf( p, fm, args);
va_end( args );
}


int WINAPI DllMain(HINSTANCE hInstance, DWORD dwReason, LPVOID lpReserved)
{
return 1;
} 



CMamaZip::CMamaZip( const char *sUnzippedFileName )
{
strcpy( m_sSourceFileName, sUnzippedFileName );
}


// throw CZipException
void CMamaZip::SwapSize( const char *sTargetFileName )
{

if (strcmp(m_sSourceFileName,sTargetFileName)==0)
    throw ( CZipException( "target name must be different than source name" ) );

// try to open in unzipped file
if ( ( inFile = open( m_sSourceFileName, _O_BINARY | _O_RDONLY ) ) == -1 )
    throw ( CZipException( "unable to open source file" ) );

if ( ( outFile = open( sTargetFileName, _O_BINARY | _O_RDWR | _O_CREAT | _O_EXCL , _S_IREAD | _S_IWRITE  ) ) == -1 )
{
    close(inFile);
    throw ( CZipException( "unable to create target file" ) );
}

ifd=inFile; ofd=outFile;
int ret = HardWork( inFile, outFile );

close( inFile );
close( outFile );

if (ret != 0)
    throw( CZipException( "problem while %s file", m_sOperation ) );
  }


 CZip::CZip( const char* sSourceFileName )
: CMamaZip( sSourceFileName ) 

 { 
m_sOperation = "zipping";   
strcpy( ifname, m_sSourceFileName );
save_orig_name = 1;
 }


 CUnzip::CUnzip( const char* sSourceFileName )
: CMamaZip( sSourceFileName ) 

 { 
m_sOperation = "unzipping";     
 }

 int CUnzip::HardWork( int inFile, int outFile )
 {
return dounzip( inFile, outFile );
 }


 int CZip::HardWork( int inFile, int outFile )
 {
return dozip( inFile, outFile );
 }

输出conf。此zip项目的类型是静态库（.lib）

我构建了这个项目并获得了zipdll.lib文件。

在另一个项目中，我设置了必要的配置，例如额外的库vs。

并包含头文件。最后我的代码是;

 #include "czip.h"
 #pragma comment(lib, "zipdll")
 . 
 .
 .
 CZip oZip(sourceFile);
 oZip.SwapSize(targetFile);

当我构建项目时，我遇到了这些错误;

  1>c:\users\16481min\desktop\czip_demo\main.cpp(91): warning C4101: 'e' : unreferenced local variable
  1>main.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: void __thiscall CMamaZip::SwapSize(char const *)" (__imp_?SwapSize@CMamaZip@@QAEXPBD@Z)
  1>main.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: __thiscall CZip::CZip(char const *)" (__imp_??0CZip@@QAE@PBD@Z)
  1>.\Debug\test_zip.exe : fatal error LNK1120: 2 unresolved externals
  ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

有什么问题？我该怎么办？有什么帮助吗？

修改

主要功能：

#include "czip.h"
#include <string>
#include <tchar.h>
#include <wininet.h>
#pragma comment(lib, "wininet")
#pragma comment(lib, "zipdll")


typedef char OSC;

using namespace std;
void ZipSend(OSC *directory, OSC *ftpServerAddr, OSC *ftpUsername, OSC *ftpPassword);

 int main()
 {

try 
{     
 ZipSend("C:\\Users\\16481MIN\\Desktop\\Foto","10.100.47.23","ftptestuser","abcd+1234");
}
catch( CZipException e )
{
    return -1;
}
return 0;
  }

  void ZipSend(OSC *directory, OSC *ftpServerAddr, OSC *ftpUsername, OSC *ftpPassword)
  {
WIN32_FIND_DATA FindFileData;
HANDLE hFind;

OSC pattern[MAX_PATH];
    OSC sourceFile[MAX_PATH];
OSC targetFile[MAX_PATH];

memset(pattern, 0x00, MAX_PATH);
sprintf(pattern,"%s\\*.*", directory);

hFind = FindFirstFile(pattern, &FindFileData);
if (hFind == INVALID_HANDLE_VALUE) 
{
} 
else 
{
    do
    {
        if(_tcscmp(FindFileData.cFileName, TEXT("."))==0 || _tcscmp(FindFileData.cFileName, TEXT(".."))==0)
            continue;

        if(FindFileData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
        {

        }
        else
        {
             memset(sourceFile, 0x00, sizeof(sourceFile));
             memset(targetFile, 0x00, sizeof(targetFile));

             string strSourceFile(FindFileData.cFileName);
             int lastindex = strSourceFile.find_last_of("."); 
             string strTargetFile(strSourceFile.substr(0, lastindex));

             sprintf(sourceFile,"%s\\%s", directory, strSourceFile.c_str());
             sprintf(targetFile, "%s\\%s.zip", directory, strTargetFile.c_str());

             try 
             {

                CZip oZip(sourceFile);
                oZip.SwapSize(targetFile);

             }
             catch( CZipException e )
             {
             }
             try 
             {
                 OSC ftpFilePath[MAX_PATH] = "";
                 strcat(ftpFilePath, "/hobim/ASYADAN/");
                 strcat(ftpFilePath, strTargetFile.c_str());
                 strcat(ftpFilePath, ".zip");

             }
             catch(exception e)
             {

             }


        }
    }
    while (FindNextFile(hFind, &FindFileData));
    FindClose(hFind);
}
   }

Answer 1

您错过了从头文件导出为DLL的文件：

#ifndef DLL_INTERNAL
#define DLL_INTERNAL __declspec( dllimport )
#endif

会将DLL_INTERNAL指定为此库要从其他库导入的内容。这在客户端（使用库的一个应用程序）代码中进行。在您的库代码中，您需要

#ifndef DLL_INTERNAL
#define DLL_INTERNAL __declspec( dllexport )
#endif

指定这些方法将从此库中 out 。

但通常情况下，MSVS框架会对这些内容进行处理，其中应用程序使用特定的定义进行编译，以判断它是否是正在编译的库（需要使用dllexport的地方）或客户端（在哪里）需要使用dllimport）

所以完整的导出/导入宏看起来像：

#ifndef DLL_COMPILED
#define DLL_INTERNAL __declspec( dllexport )
else
#define DLL_INTERNAL __declspec( dllimport )
#endif

并且您需要注意在编译阶段（作为编译器的参数，通常使用DLL_COMPILED）指定/DDLL_COMPILED。

Answer 2

链接器正在寻找CMamaZip::SwapSize(char const *)输入 - char const * 在czip.h中，方法是 - 带有输入的SwapSize( const char *sTargetFileName ) - const char *

错误LNK2019和致命错误LNK1120：2个未解析的外部

2 个答案: