DLL导出函数错点错

[tr821021]

def文件; PrinterDll.def : Declares the module parameters for the DLL.

LIBRARY "PrinterDll"
DESCRIPTION 'PrinterDll Windows Dynamic Link Library'

EXPORTS
Init @1
CheckPrinter @2
WarningCheck @3
CheckPrinterTotalNum @4
PrintImage @5
.h文件：
_declspec(dllexport) int Init();
_declspec(dllexport) int CheckPrinter();
_declspec(dllexport) int WarningCheck ();
_declspec(dllexport) int CheckPrinterTotalNum();
_declspec(dllexport) int PrintImage(char* str,int paperNum);

.cpp
_declspec(dllexport) int CheckPrinter(){}
_declspec(dllexport) int WarningCheck (){}
_declspec(dllexport) int CheckPrinterTotalNum(){}
_declspec(dllexport) int PrintImage(char* str,int paperNum){}
错误：
Linking...
.\PrinterDll.def : warning LNK4022: cannot find unique match for symbol "Init"
.\PrinterDll.def : warning LNK4002: "public: int __thiscall PrinterFun::Init(void)" (?Init@PrinterFun@@QAEHXZ) defined in .\Debug\PrinterFun.obj
.\PrinterDll.def : warning LNK4002: "protected: void __thiscall CString::Init(void)" (?Init@CString@@IAEXXZ) defined in C:\Program Files\Microsoft Visual Studio\VC98\MFC\LIB\mfc42d.lib
LINK : fatal error LNK1152: cannot resolve one or more undecorated symbols
LINK : fatal error LNK1141: failure during build of exports file
Error executing link.exe.

PrinterDll.dll - 2 error(s), 3 warning(s)
麻烦具体告诉下如何导出函数，导出类就不要说了，我会，现在我就是导出函数然后做个COM接口去调用
麻烦详细告诉下如何导出函数，COM里又该如何调用他

[ouyh12345]

如果在def文件导出了的话，则头文件、源文件里的_declspec(dllexport)都要去掉

[ouyh12345]

另外，源文件里，没有实现Init函数？

[快乐鹦鹉]

.cpp中怎么没有Init函数体呢？

[tr821021]

现在就是我用类写的DLL在COM我就是找不到接口，
--------------------Configuration: IPrinterCom - Win32 Debug--------------------
Compiling...
IFun.cpp
Linking...
Creating library Debug/IPrinterCom.lib and object Debug/IPrinterCom.exp
IFun.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) int __cdecl Init(void)" (__imp_?Init@@YAHXZ)
Debug/IPrinterCom.dll : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

IPrinterCom.dll - 2 error(s), 0 warning(s)

[scq2099yt]

up

[ouyh12345]

看2楼和3楼的回复

[快乐鹦鹉]

你没有写Init的函数体阿

[tr821021]

2楼回复我取掉DEF文件定义，查看是得到这5个函数导出了，可COM里却还是找不到接口啊
Init我实现过了

[tr821021]

_declspec(dllimport) int Init();
STDMETHODIMP CIFun::CallDll (int *pVal)
{
*pVal = Init();
return S_OK;
}

Linking...
Creating library Debug/IPrinterCom.lib and object Debug/IPrinterCom.exp
IFun.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) int __cdecl Init(void)" (__imp_?Init@@YAHXZ)
Debug/IPrinterCom.dll : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

IPrinterCom.dll - 2 error(s), 0 warning(s)

我该添加的肯定都添加过lib文件了，头文件包含过了

[快乐鹦鹉]

可COM里却还是找不到接口啊
===你在工程中有没有在project->setting的link页中引入你的动态库的lib文件呢？

[ouyh12345]

#include "PrinterDll.h"
#pragma comment(lib, "PrinterDll.lib")

STDMETHODIMP CIFun::CallDll (int *pVal)
{
*pVal = Init();
return S_OK;
}

[jameshooo]

extern "C" int Init()
除了没实现的Init函数，其它导出函数都要用extern "C"修饰符

[cnzdgs]

要导入lib文件，可以加在项目属性连接器设置里面，或者：
#pragma comment(lib, "PrinterDll.lib")

另外用_declspec(dllexport)导出并且隐式加载时不需要def文件。

[高山-流水]

1:函数前加extern "C"
2：Init()函数没定义
3：导入函数库#pragma comment(lib, "PrinterDll.lib")

[tr821021]

我想问下DLL里int PrintImage(char* str,int paperNum)
我在COM里STDMETHOD(CallDllPrintImage)(/*[in]*/char* str,int paperNum,/*[out retval]*/ int *pVal4);

我知道COM里好像不让用char*那该如何做啊，总不能DLL也给修改了吧
知道的指点我下吧，项目马上要出来了

[Kudeet]

你应该注意调用DLL的方法，看www.vckbase.com的示例

[吹雪]

COM里可以用BYTE来代替char

[flm007]

并没有去实现，已经帮你调试好