COM技术初探（二）

//MathCOM.idl文件
// MathCOM.idl : IDL source for MathCOM.dll
//
// This file will be processed by the MIDL tool to
// produce the type library (MathCOM.tlb) and marshalling code.
import "oaidl.idl";
import "ocidl.idl";
[
uuid(FAEAE6B7-67BE-42a4-A318-3256781E945A),
helpstring("ISimpleMath Interface"),
object,
pointer_default(unique)
]
interface ISimpleMath : IUnknown
{
HRESULT Add([in]int nOp1,[in]int nOp2,[out,retval]int * pret);
HRESULT Subtract([in]int nOp1,[in]int nOp2,[out,retval]int * pret);
HRESULT Multiply([in]int nOp1,[in]int nOp2,[out,retval] int * pret);
HRESULT Divide([in]int nOp1,[in]int nOp2,[out,retval]int * pret);
};

[
uuid(01147C39-9DA0-4f7f-B525-D129745AAD1E),
helpstring("IAdvancedMath Interface"),
object,
pointer_default(unique)
]
interface IAdvancedMath : IUnknown
{
HRESULT Factorial([in]int nOp1,[out,retval]int * pret);
HRESULT Fabonacci([in]int nOp1,[out,retval]int * pret);
};
[
uuid(CA3B37EA-E44A-49b8-9729-6E9222CAE844),
version(1.0),
helpstring("MATHCOM 1.0 Type Library")
]
library MATHCOMLib
{
importlib("stdole32.tlb");
importlib("stdole2.tlb");

[
uuid(3BCFE27E-C88D-453C-8C94-F5F7B97E7841),
helpstring("MATHCOM Class")
]
coclass MATHCOM
{
[default] interface ISimpleMath;
interface IAdvancedMath;
};
};

//MathCOM.def文件
; MathCOM.def : Declares the module parameters.

LIBRARY       "MathCOM.DLL"

EXPORTS
DllCanUnloadNow      @1 PRIVATE
DllGetClassObject    @2 PRIVATE
DllRegisterServer    @3 PRIVATE
DllUnregisterServer @4 PRIVATE

// MATHCOM.cpp : Defines the entry point for the DLL application.
//
#include "stdafx.h"
#include <objbase.h>
#include <initguid.h>
#include "MathCOM.h"

//standard self-registration table
const char * g_RegTable[][3]={
{"CLSID//{3BCFE27E-C88D-453C-8C94-F5F7B97E7841}",0,"MathCOM"},
{"CLSID//{3BCFE27E-C88D-453C-8C94-F5F7B97E7841}//InprocServer32",
0,
(const char * )-1 /*表示文件名的值*/},
{"CLSID//{3BCFE27E-C88D-453C-8C94-F5F7B97E7841}//ProgID",0,"tulip.MathCOM.1"},
{"tulip.MathCOM.1",0,"MathCOM"},
{"tulip.MathCOM.1//CLSID",0,"{3BCFE27E-C88D-453C-8C94-F5F7B97E7841}"},
};

HINSTANCE   g_hinstDll;

BOOL APIENTRY DllMain( HANDLE hModule,
DWORD   ul_reason_for_call,
LPVOID lpReserved
)
{
g_hinstDll=(HINSTANCE)hModule;
return TRUE;
}

/*********************************************************************
* Function Declare : DllUnregisterServer
* Explain : self-unregistration routine
* Parameters :
* void --
* Return :
* STDAPI   --
* Author : tulip
* Time : 2003-10-29 19:07:42
*********************************************************************/
STDAPI DllUnregisterServer(void)
{
HRESULT hr=S_OK;
char szFileName [MAX_PATH];
::GetModuleFileName(g_hinstDll,szFileName,MAX_PATH);

int nEntries=sizeof(g_RegTable)/sizeof(*g_RegTable);
for(int i =0;SUCCEEDED(hr)&&i<nEntries;i++)
{
const char * pszKeyName=g_RegTable[i][0];
long err=::RegDeleteKey(HKEY_CLASSES_ROOT,pszKeyName);
if(err!=ERROR_SUCCESS)
hr=S_FALSE;
}

return hr;
}

/*********************************************************************
* Function Declare : DllRegisterServer
* Explain : self Registration routine
* Parameters :
* void --
* Return :
* STDAPI   --
* Author : tulip
* Time : 2003-10-29 19:43:51
*********************************************************************/
STDAPI DllRegisterServer(void)
{
HRESULT hr=S_OK;
char szFileName [MAX_PATH];
::GetModuleFileName(g_hinstDll,szFileName,MAX_PATH);

int nEntries=sizeof(g_RegTable)/sizeof(*g_RegTable);
for(int i =0;SUCCEEDED(hr)&&i<nEntries;i++)
{
const char * pszKeyName=g_RegTable[i][0];
const char * pszValueName=g_RegTable[i][1];
const char * pszValue=g_RegTable[i][2];

if(pszValue==(const char *)-1)
{
pszValue=szFileName;
}

HKEY hkey;
long err=::RegCreateKey(HKEY_CLASSES_ROOT,pszKeyName,&hkey);
if(err==ERROR_SUCCESS)
{
err=::RegSetValueEx( hkey,
pszValueName,
0,
REG_SZ,
( const BYTE*)pszValue,
( strlen(pszValue)+1 ) );
::RegCloseKey(hkey);
}
if(err!=ERROR_SUCCESS)
{
::DllUnregisterServer();
hr=E_FAIL;
}

}
return hr;
}

STDAPI DllGetClassObject(REFCLSID rclsid ,REFIID riid,void **ppv)
{
return CLASS_E_CLASSNOTAVAILABLE;
}

STDAPI DllCanUnloadNow(void)
{
return E_FAIL;
}

1) Math.h文件
/*@**#---2003-10-29 21:33:44 (tulip)---#**@

#include "interface.h"*/

#include "MathCOM.h"//新增加的，以替换上面的东东

class CMath : public ISimpleMath,
public IAdvancedMath
{
private:
ULONG m_cRef;

private:
int calcFactorial(int nOp);
int calcFabonacci(int nOp);

public:
CMath();
//IUnknown Method
STDMETHOD(QueryInterface)(REFIID riid, void **ppv);
STDMETHOD_(ULONG, AddRef)();
STDMETHOD_(ULONG, Release)();

// ISimpleMath Method
STDMETHOD (Add)(int nOp1, int nOp2,int * pret);
STDMETHOD (Subtract)(int nOp1, int nOp2,int *pret);
STDMETHOD (Multiply)(int nOp1, int nOp2,int *pret);
STDMETHOD (Divide)(int nOp1, int nOp2,int * pret);

// IAdvancedMath Method
STDMETHOD (Factorial)(int nOp,int *pret);
STDMETHOD (Fabonacci)(int nOp,int *pret);
};

2) Math.cpp文件
/*@**#---2003-10-29 21:32:35 (tulip)---#**@

#include "interface.h"   */
#include "math.h"

STDMETHODIMP CMath::QueryInterface(REFIID riid, void **ppv)
{// 这里这是实现dynamic_cast的功能，但由于dynamic_cast与编译器相关。
if(riid == IID_ISimpleMath)
*ppv = static_cast<ISimpleMath *>(this);
else if(riid == IID_IAdvancedMath)
*ppv = static_cast<IAdvancedMath *>(this);
else if(riid == IID_IUnknown)
*ppv = static_cast<ISimpleMath *>(this);
else {
*ppv = 0;
return E_NOINTERFACE;
}

reinterpret_cast<IUnknown *>(*ppv)->AddRef(); //这里要这样是因为引用计数是针对组件的
return S_OK;
}

STDMETHODIMP_(ULONG) CMath::AddRef()
{
return ++m_cRef;
}

STDMETHODIMP_(ULONG) CMath::Release()
{
ULONG res = --m_cRef; // 使用临时变量把修改后的引用计数值缓存起来
if(res == 0)  // 因为在对象已经销毁后再引用这个对象的数据将是非法的
delete this;
return res;
}

STDMETHODIMP CMath::Add(int nOp1, int nOp2,int * pret)
{
*pret=nOp1+nOp2;
return S_OK;
}

STDMETHODIMP CMath::Subtract(int nOp1, int nOp2,int * pret)
{
*pret= nOp1 - nOp2;
return S_OK;
}

STDMETHODIMP CMath::Multiply(int nOp1, int nOp2,int * pret)
{
*pret=nOp1 * nOp2;
return S_OK;
}

STDMETHODIMP CMath::Divide(int nOp1, int nOp2,int * pret)
{
*pret= nOp1 / nOp2;
return S_OK;
}

int CMath::calcFactorial(int nOp)
{
if(nOp <= 1)
return 1;

return nOp * calcFactorial(nOp - 1);
}

STDMETHODIMP CMath::Factorial(int nOp,int * pret)
{
*pret=calcFactorial(nOp);
return S_OK;
}

int CMath::calcFabonacci(int nOp)
{
if(nOp <= 1)
return 1;

return calcFabonacci(nOp - 1) + calcFabonacci(nOp - 2);
}

STDMETHODIMP CMath::Fabonacci(int nOp,int * pret)
{
*pret=calcFabonacci(nOp);
return S_OK;
}

CMath::CMath()
{
m_cRef=0;
}

#include "math.h"
#include "MathCOM_i.c"

/*********************************************************************
* Function Declare : DllGetClassObject
* Explain :
* Parameters :
* REFCLSID rclsid   --
* REFIID riid --
* void **ppv --
* Return :
* STDAPI   --
* Author : tulip
* Time : 2003-10-29 22:03:53
*********************************************************************/
STDAPI DllGetClassObject(REFCLSID rclsid ,REFIID riid,void **ppv)
{
static CMath *pm_math=new CMath;
if(rclsid==CLSID_MATHCOM)
return pm_math->QueryInterface(riid,ppv);

return CLASS_E_CLASSNOTAVAILABLE;
}

//main.cpp文件
#include <windows.h>
#include "../MathCOM.h"//这里请注意路径
#include "../MathCOM_i.c"//这里请注意路径
#include <iostream>
using namespace std;

void main(void)
{
//初始化COM库
HRESULT hr=::CoInitialize(0);
ISimpleMath * pSimpleMath=NULL;
IAdvancedMath * pAdvancedMath=NULL;

int nReturnValue=0;

hr=::CoGetClassObject(CLSID_MATHCOM,
CLSCTX_INPROC,
NULL,IID_ISimpleMath,
(void **)&pSimpleMath);
if(SUCCEEDED(hr))
{
hr=pSimpleMath->Add(10,4,&nReturnValue);
if(SUCCEEDED(hr))
cout << "10 + 4 = " <<nReturnValue<< endl;
nReturnValue=0;
}

// 查询对象实现的接口IAdvancedMath
hr=pSimpleMath->QueryInterface(IID_IAdvancedMath, (void **)&pAdvancedMath);
if(SUCCEEDED(hr))
{
hr=pAdvancedMath->Fabonacci(10,&nReturnValue);
if(SUCCEEDED(hr))
cout << "10 Fabonacci is " << nReturnValue << endl;
}
pAdvancedMath->Release();
pSimpleMath->Release();

::CoUninitialize();

::system("pause");
return ;

}

Linking...
Creating library Debug/COM_1.lib and object Debug/COM_1.exp
LIBCD.lib(crt0.obj) : error LNK2001: unresolved external symbol _main
Debug/COM_1.exe : fatal error LNK1120: 1 unresolved externals

kernel32.lib user32.lib gdi32.lib winspool.lib comdlg32.lib advapi32.lib shell32.lib
ole32.lib oleaut32.lib uuid.lib odbc32.lib odbccp32.lib /nologo /dll /incremental:yes
/pdb:"Debug/COM_1.pdb" /debug /machine:I386 /out:"Debug/COM_1.dll" /implib:"Debug/COM_1.lib"
/pdbtype:sept

//com_1.cpp
#include <objbase.h>
BOOL APIENTRY DllMain(HANDLE hModule, DWORD dwReason, void* lpReserved)
{
HANDLE g_hModule;
switch(dwReason)
{
case DLL_PROCESS_ATTACH:
g_hModule = (HINSTANCE)hModule;
break;
case DLL_PROCESS_DETACH:
g_hModule=NULL;
break;
}
}

#include <objbase.h>

extern "C" __declspec(dllexport)   void tulip (void)
{
::MessageBox(NULL,"ok","I''am fine",MB_OK);
}

BOOL APIENTRY DllMain(HANDLE hModule, DWORD dwReason, void* lpReserved)
{
HANDLE g_hModule;
switch(dwReason)
{
case DLL_PROCESS_ATTACH:
g_hModule = (HINSTANCE)hModule;
break;
case DLL_PROCESS_DETACH:
g_hModule=NULL;
break;
}

return TRUE;
}

#include <windows.h>

int main(void)
{
//定义一个函数指针
typedef void (   * TULIPFUNC )(void);

//定义一个函数指针变量
TULIPFUNC tulipFunc;

//加载我们膁ll
HINSTANCE hinst=::LoadLibrary("COM_1.dll");

//找到dll的tulip函数
tulipFunc=(TULIPFUNC)GetProcAddress(hinst,"tulip");

//调用dll里的函数
tulipFunc();

return 0;
}

#include <objbase.h>
#include "header.h"//看到没有，这就是我们增加的头文件

extern "C" __declspec(dllexport)   void tulip (void)
{
::MessageBox(NULL,"ok","I''am fine",MB_OK);
}

BOOL APIENTRY DllMain(HANDLE hModule, DWORD dwReason, void* lpReserved)
{
HANDLE g_hModule;
switch(dwReason)
{
case DLL_PROCESS_ATTACH:
g_hModule = (HINSTANCE)hModule;
break;
case DLL_PROCESS_DETACH:
g_hModule=NULL;
break;
}

return TRUE;
}

extern "C" __declspec(dllexport)   void tulip (void);

#include <windows.h>
#include "../header.h"//注意路径

//注意路径，加载 COM_1.lib 的另一种方法是 Project | setting | link 设置里
#pragma comment(lib,"COM_1.lib")

int main(void)
{
tulip();//只要这样我们就可以调用dll里的函数了

return 0;
}