请问如何用VC调用VC编写的COM?

[yugx]

我用ClassWizard-->Add Class-->From a type library会生成一些从COleDispatchDriver派生的封装类。类名Imycom. 然后用以下方法调用它：
1. 使用时首先定义类实例对象 Imycom nnn，
2. 然后用类方法nnn.CreateDispatch(clsid)创建。
3. 接着就可以调用我COM中的sum方法 ret = nnn.sum(1, 2)
结果ret的值不对，
我估计是1,2出错， 请问应该怎么写？

[houzh]

bool VSConnect(LPSTR cServerAddr)
{
HRESULT hr;

if(ievs_channel!=NULL) ievs_channel->Release();

if(strcmp(cServerAddr,"")==0) //local connection CoCreateInstance
{
IUnknown* pUnk;
hr=CoCreateInstance(CLSID_EVS_Channel,NULL,CLSCTX_SERVER,IID_IUnknown,(void **)&pUnk);
if (hr!=S_OK)
return false;
hr=pUnk->QueryInterface(IID_IEVS_Channel,(void **)&ievs_channel);
if (hr!=S_OK)
{
pUnk->Release();
return false;
}
}
else
{// remote connection CoCreateInstanceEx
CString sTemp;
sTemp = cServerAddr;
COSERVERINFO coserv;
coserv.dwReserved1=0;
coserv.dwReserved2=0;
_bstr_t bst;
bst=sTemp;
coserv.pwszName=bst;
coserv.pAuthInfo=NULL;

MULTI_QI mqi;
IID req_iid=IID_IUnknown;
mqi.pIID=&req_iid;
mqi.pItf=NULL;
CoCreateInstanceEx(CLSID_EVS_Channel,NULL,CLSCTX_SERVER
,&coserv,1,&mqi);

if (mqi.hr!=S_OK)
return false;
hr=mqi.pItf->QueryInterface(IID_IEVS_Channel,(void **)&ievs_channel);
if (hr!=S_OK)
{
mqi.pItf->Release();
return false;
}
mqi.pItf->Release();
}
return true;
}