一个Debug-Print功能可以统治它们

Question

我的情况是我的代码中有几个不同的结构,我想要打印到控制台.

三个例子(几百个):

typedef struct ReqCntrlT    /* Request control record */
{
int             connectionID;
int             dbApplID;
char            appDescr[MAX_APPDSCR];
int             reqID;
int         resubmitFlag;
unsigned int    resubmitNo;
char            VCIver[MAX_VCIVER];
int             loginID;

}   ReqCntrlT;

//---------------------------------------------   

typedef struct      /* Connection request data block */
{
    char            userID[MAX_USRID];
    char            password[MAX_PWDID];

}   CnctReqDataT;

//---------------------------------------------   

typedef struct {
    char            userID[LOGIN_MAX_USERID];
    char            closure;
    int             applVersion;
    int             authorizationDataLength;
    void            *authorizationData; }   LoginReqDataT;

所以我想拥有的是一个调试函数,它只需要一个struct作为Parameter并输出结构的所有成员,如下所示:

LoginReqDataT* foo = new LoginReqDataT;
foo->applVersion = 123;
//...
debugPrintMe(foo);

CnctReqDataT* bar = new CnctReqDataT;
strcpy(bar->userID, "123");
strcpy(bar->password, "mypwd");
debugPrintMe(bar);

我现在拥有的是一个无穷无尽的功能,它正在做这样的事情:

template <class T>
void debugPrintMe(T myvar)
{
    if (!DEBUG) return;

    if (typeid(T) == typeid(ReqCntrlT*))
    {
        ReqCntrlT* r = (ReqCntrlT*)myvar; 
        cout << "reqControl: " << endl 
             << "\tconnectionID: " << r->connectionID << endl
             << "\tdbApplID: " << r->dbApplID << endl
             //...
             << "\tloginID: " << r->loginID << endl << endl;
    }
    else if (typeid(T) == typeid(CallBkAppDataT*))
    {
        CallBkAppDataT* c = (CallBkAppDataT*)myvar; 
        cout << "appData: " << endl
             << "\tappRespBlockSize " << c->appRespBlockSize << endl
             //...
             << "\tstreamType: " << c->streamType << endl << endl;
    }
    //... and so on
}

有没有更优雅的方式来做到这一点？

Answer 1

是的,肯定有更优雅的方式(... else if (typeid(T) == ...？哎呀!).你可以operator <<()为你写一些structs.这使你的debugPrintMe()功能好和通用的,也可以让你流的结构来cout,cerr中,记录器,一ostringstream,...

这是一个让你入门的例子:

std::ostream& operator <<(std::ostream& os, const ReqCntrlT& r)
{
    os << "reqControl"
        << "\n\tconnectionID: " << r.connectionID 
        << "\n\tdbApplID: " << r.dbApplID 
        << "\n\tappDescr: " << r.appDescr
        << "\n\treqID: " << r.reqID
        << "\n\tresubmitFlag: " << r.resubmitFlag
        << "\n\tresubmitNo: " << r.resubmitNo
        << "\n\tVCIver: " << r.VCIver
        << "\n\tloginID: " << r.loginID
        << '\n';
    return os;
}

template <class T>
void debugPrintMe(const T& myvar)
{
    if (DEBUG)
    {
        std::cout << myvar << std::endl;
    }
}

int main()
{
    ReqCntrlT r;

    // [...]

    debugPrintMe(r);

    return 0;
}