VS2019 C++ 错误 C2280 尝试在l中引用已删除的函数

Question

我是 C++ 入门级。尝试构建一个不是我创建的项目。插入一些丢失的库后，我遇到了 C2280 错误：“CBrush::CBrush(const CBrush &)”：试图引用已删除的函数”。我对如何开始深入了解问题感到困惑。

static COLORREF ClrList[] = { RGB(128,0,0),         // Red
                          RGB(128,128,0),       // Dark yellow
                          RGB(0,200,0),         // Green
                          RGB(0,200,200),       // Cyan
                          RGB(0,0,255),         // Blue
                          RGB(125,42,249),      // Purple
                          RGB(255,128,0),       // Orange
                          RGB(0,0,0) };         // Black

static CBrush BrushList[] = { CBrush(ClrList[0]),   //Error 2280
                              CBrush(ClrList[1]),
                              CBrush(ClrList[2]),
                              CBrush(ClrList[3]),
                              CBrush(ClrList[4]),
                              CBrush(ClrList[5]),
                              CBrush(ClrList[6]),
                              CBrush(ClrList[7]) };

CBrush 类声明：

    class CBrush : public CGdiObject
{
    DECLARE_DYNAMIC(CBrush)

public:
    static CBrush* PASCAL FromHandle(HBRUSH hBrush);

// Constructors
    CBrush();
    CBrush(COLORREF crColor);             // CreateSolidBrush
    CBrush(int nIndex, COLORREF crColor); // CreateHatchBrush
    explicit CBrush(CBitmap* pBitmap);          // CreatePatternBrush

    BOOL CreateSolidBrush(COLORREF crColor);
    BOOL CreateHatchBrush(int nIndex, COLORREF crColor);
    BOOL CreateBrushIndirect(const LOGBRUSH* lpLogBrush);
    BOOL CreatePatternBrush(CBitmap* pBitmap);
    BOOL CreateDIBPatternBrush(HGLOBAL hPackedDIB, UINT nUsage);
    BOOL CreateDIBPatternBrush(const void* lpPackedDIB, UINT nUsage);
    BOOL CreateSysColorBrush(int nIndex);

// Attributes
    operator HBRUSH() const;
    int GetLogBrush(LOGBRUSH* pLogBrush);

// Implementation
public:
    virtual ~CBrush();
#ifdef _DEBUG
    virtual void Dump(CDumpContext& dc) const;
#endif
};

我不熟悉 inl 文件，但我认为这是内联声明：

_AFXWIN_INLINE CBrush::operator HBRUSH() const
    { return (HBRUSH)(this == NULL ? NULL : m_hObject); }
_AFXWIN_INLINE CBrush* PASCAL CBrush::FromHandle(HBRUSH hBrush)
    { return (CBrush*) CGdiObject::FromHandle(hBrush); }
_AFXWIN_INLINE CBrush::CBrush()
    { }
_AFXWIN_INLINE CBrush::~CBrush()
    { }
_AFXWIN_INLINE BOOL CBrush::CreateSolidBrush(COLORREF crColor)
    { return Attach(::CreateSolidBrush(crColor)); }
_AFXWIN_INLINE BOOL CBrush::CreateHatchBrush(int nIndex, COLORREF crColor)
    { return Attach(::CreateHatchBrush(nIndex, crColor)); }
_AFXWIN_INLINE BOOL CBrush::CreateBrushIndirect(const LOGBRUSH* lpLogBrush)
    { return Attach(::CreateBrushIndirect(lpLogBrush)); }
_AFXWIN_INLINE BOOL CBrush::CreatePatternBrush(CBitmap* pBitmap)
    { return Attach(::CreatePatternBrush((HBITMAP)pBitmap->GetSafeHandle())); }
_AFXWIN_INLINE BOOL CBrush::CreateDIBPatternBrush(const void* lpPackedDIB, UINT nUsage)
    { return Attach(::CreateDIBPatternBrushPt(lpPackedDIB, nUsage)); }
_AFXWIN_INLINE BOOL CBrush::CreateSysColorBrush(int nIndex)
    { return Attach(::GetSysColorBrush(nIndex)); }
_AFXWIN_INLINE int CBrush::GetLogBrush(LOGBRUSH* pLogBrush)
    { ASSERT(m_hObject != NULL);
        return ::GetObject(m_hObject, sizeof(LOGBRUSH), pLogBrush); }

Answer 1

根据 Microsoft 的文档，您需要为

CBrush

对象添加复制构造函数。

标准 C++ 默认类复制构造函数执行逐个成员的复制。如果您的类的复制构造函数需要但不可用，则私有 CObject 复制构造函数的存在可保证出现编译器错误消息。如果您的类需要此功能，请提供复制构造函数。