c++ - 无法访问类 'CObject' 中声明的私有(private)成员？

Question

class EventDataValue {
public:
    enum Types {
        NONE,
        INT,
        STRING,
        DOUBLE,
        ULONG
    };

    EventDataValue() { this->Type = NONE; }
    EventDataValue( const EventDataValue &s ) { 
        this->Type = s.Type;

        if (this->Type == INT) 
            this->i = s.i;
        else if (this->Type == STRING)
            this->s = s.s;
        else if (this->Type == DOUBLE)
            this->d = s.d;
        else if (this->Type == ULONG)
            this->ul = s.ul;
    }

    EventDataValue& operator=( const EventDataValue &s ) { 
        this->Type = s.Type;

        if (this->Type == INT) 
            this->i = s.i;
        else if (this->Type == STRING)
            this->s = s.s;
        else if (this->Type == DOUBLE)
            this->d = s.d;
        else if (this->Type == ULONG)
            this->ul = s.ul;

        return *this; 
    }


    EventDataValue(int value) {
        this->Type = INT;
        this->i = value;
    }

    EventDataValue(CString &value) {
        this->Type = STRING;
        this->s = value;
    }

    EventDataValue(LPCTSTR value) {
        this->Type = STRING;
        this->s = CString(value);
    }

    EventDataValue(double value) {
        this->Type = DOUBLE;
        this->d = value;
    }

    EventDataValue(unsigned long value) {
        this->Type = ULONG;
        this->ul = value;
    }

    ~EventDataValue() { }

    operator int(void) const {
        return this->i;
    }

    operator CString(void) const {
        return this->s;
    }

    operator double(void) const {
        return this->d;
    }

    operator unsigned long(void) const {
        return this->ul;
    }


    Types Type;
    int i;
    CString s;
    double d;
    unsigned long ul;
};

class EventData {
public:
    EventData(CString strEventCode, CString &strSessionId, int nFlowId = 0) {
        this->Add(CString(_T("tp")), strEventCode);
        this->Add(CString(_T("ss")), strSessionId);
        this->Add(CString(_T("ts")), (int)std::time(0));

        if (nFlowId != 0)
            this->Add(CString(_T("fl")), nFlowId);
    }

    template <typename T>
    void Add(CString name, T value) {
        EventDataValue event_value(value);

        if (cMap.Lookup(name, NULL) == TRUE)
            return;

        cMap[name] = value;
    }

    CMap<CString, CString, EventDataValue, EventDataValue> cMap;
};

class Events {
public:
    Events() { }
    ~Events() { }

    void Add(EventData ev) {
        this->aEvents.Add(ev);
    }

    CStringW Serialize() {
        CStringW strOutput;
        INT_PTR i, j;

        if (_tcscmp(API_FORMAT, FORMAT_JSON) == 0) {
            for (i = 0; i != this->aEvents.GetCount(); i++) {
                EventData ev = this->aEvents[i];

                strOutput += L"{";

                j = 0;

                POSITION pos = ev.cMap.GetStartPosition();

                while (pos != NULL) {
                    CString key;
                    EventDataValue value;

                    ev.cMap.GetNextAssoc( pos, key, value );

                    strOutput += StringFormat(_T("\"%s\": "), key.GetString());

                    if (value.Type == EventDataValue::STRING) {
                        CString str = value;
                        strOutput += Enquoute(str);
                    } else if (value.Type == EventDataValue::INT) {
                        int n = value;
                        strOutput += StringFormat(_T("%d"), n);
                    } else if (value.Type == EventDataValue::DOUBLE) {
                        double d = value;
                        strOutput += StringFormat(_T("%d"), static_cast<int>(d));
                    } else if (value.Type == EventDataValue::ULONG) {
                        ULONG ul = value;
                        strOutput += StringFormat(_T("%u"), ul);
                    }

                    if (j++ < ev.cMap.GetCount() - 1)
                        strOutput += _T(",");
                }

                strOutput += _T("}");
            }
        } else {
            for (i = 0; i != this->aEvents.GetCount(); i++) {
                EventData ev = this->aEvents[i];

                strOutput += _T("<Event>");

                j = 0;

                POSITION pos = ev.cMap.GetStartPosition();

                while (pos != NULL) {
                    CString key;
                    EventDataValue value;

                    ev.cMap.GetNextAssoc( pos, key, value );

                    strOutput += StringFormat(_T("<%s>"), key.GetString());

                    if (value.Type == EventDataValue::STRING) {
                        CString str = value;
                        strOutput += str;
                    } else if (value.Type == EventDataValue::INT) {
                        int n = value;
                        strOutput += StringFormat(_T("%d"), n);
                    } else if (value.Type == EventDataValue::DOUBLE) {
                        double d = value;
                        strOutput += StringFormat(_T("%d"), static_cast<int>(d));
                    } else if (value.Type == EventDataValue::ULONG) {
                        ULONG ul = value;
                        strOutput += StringFormat(_T("%u"), ul);
                    }

                    strOutput += StringFormat(_T("</%s>"), key.GetString());
                }

                strOutput += _T("</Event>");
            }

        }

        return strOutput;
    }

    CArray<EventData> aEvents;
};

谁能告诉我为什么在编译时会出现以下错误？

1>c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\afxtempl.h(1329): error C2248: 'CObject::CObject' : cannot access private member declared in class 'CObject'
1>          c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\afx.h(559) : see declaration of 'CObject::CObject'
1>          c:\program files (x86)\microsoft visual studio 11.0\vc\atlmfc\include\afx.h(534) : see declaration of 'CObject'
1>          This diagnostic occurred in the compiler generated function 'CMap<KEY,ARG_KEY,VALUE,ARG_VALUE>::CMap(const CMap<KEY,ARG_KEY,VALUE,ARG_VALUE> &)'
1>          with
1>          [
1>              KEY=CString,
1>              ARG_KEY=CString,
1>              VALUE=EventDataValue,
1>              ARG_VALUE=EventDataValue
1>          ]

Answer 1

void Add(EventData ev) {
    this->aEvents.Add(ev);
}

这必须是Add(EventData& ev)。您的 EventData 类没有非默认复制构造函数或复制赋值运算符，并且有一个不可复制的成员 (CMap)。这使得 EventData 不可复制。所以你不能按值传递它，因为那样必须制作一个拷贝，而你不能这样做，因为该类是不可复制的。