【正文】 olor){ itsColor = color。}void WagTail(){ cout private:myColor itsColor。}。Mammal::Mammal(): itsAge(1)，itsWeight(5){cout Mammal::~Mammal(){cout Dog::Dog(): itsColor(WHITE){ cout Dog::~Dog(){ cout return 0。}程序運行輸出： Mammal constructor...Dog constructor...Mammal sound!Tail wagging...Fido is 1 years old Dog destructor...Mammal destructor...77 定義一個基類，構(gòu)造其派生類，在構(gòu)造函數(shù)中輸出提示信息，觀察構(gòu)造函數(shù)的執(zhí)行情況。解：include class BaseClass { public: BaseClass()。}。BaseClass::BaseClass(){ cout class DerivedClass : public BaseClass { public:DerivedClass()。}。DerivedClass::DerivedClass(){cout void main(){DerivedClass d。}程序運行輸出： 構(gòu)造基類對象!構(gòu)造派生類對象!78 定義一個Document類，有name成員變量，從Document派生出Book類，增加PageCount變量。解：include include class Document { public: Document(){}。Document(char *name)。char *Name。// Document PrintNameOf()。// Print name.}。Document::Document(char *name){Name = new char[ strlen(name)+ 1 ]。strcpy(Name, name)。}。void Document::PrintNameOf(){cout }class Book : public Document { public: Book(char *name, long pagecount)。void PrintNameOf()。private: long PageCount。}。Book::Book(char *name, long pagecount):Document(name){ PageCount = pagecount。} void Book::PrintNameOf(){ cout void main(){ Document a(”Document1“)。Book b(”Book1“,100)。()。} 程序運行輸出： Name of book: Book179 定義基類Base，有兩個共有成員函數(shù)fn1()、fn2()，私有派生出Derived類，如果想在Derived類的對象中使用基類函數(shù)fn1()，應怎么辦？解： class Base { public: int fn1()const { return 1。} int fn2()const { return 2。} }。class Derived : private Base { public:int fn1(){ return Base::fn1()。}。int fn2(){ return Base::fn2()。}。}。void main(){Derived a。()。}710 定義object類，有weight屬性及相應的操作函數(shù)，由此派生出box類，增加Height和width屬性及相應的操作函數(shù)，聲明一個box對象，觀察構(gòu)造函數(shù)與析構(gòu)函數(shù)的調(diào)用順序。解：include class object { private: int Weight。public: object(){cout int GetWeight(){ return Weight。} void SetWeight(int n){ Weight = n。}~object(){ cout class box : public object { private:int Height,Width。public: box(){cout int GetHeight(){ return Height。} void SetHeight(int n){ Height = n。} int GetWidth(){ return Width。} void SetWidth(int n){ Width = n。}~box(){ cout void main(){ box a。}程序運行輸出： 構(gòu)造object對象 構(gòu)造box對象 析構(gòu)box對象 析構(gòu)object對象711 定義一個基類BaseClass，從它派生出類DerivedClass，BaseClass有成員函數(shù)fn1()、fn2()，DerivedClass也有成員函數(shù)fn1()、fn2()，在主程序中定義一個DerivedClass的對象，分別用DerivedClass的對象以及BaseClass和DerivedClass的指針來調(diào)用fn1()、fn2()，觀察運行結(jié)果。解：include class BaseClass { public: void fn1()。void fn2()。}。void BaseClass::fn1(){ cout class DerivedClass : public BaseClass { public: void fn1()。void fn2()。}。void DerivedClass::fn1(){cout void DerivedClass::fn2(){cout void main(){DerivedClass aDerivedClass。DerivedClass *pDerivedClass = amp。aDerivedClass。BaseClass *pBaseClass = amp。aDerivedClass。()。()。pBaseClassfn1()。pBaseClassfn2()。pDerivedClassfn1()。pDerivedClassfn2()。}程序運行輸出： 調(diào)用派生類的函數(shù)fn1()調(diào)用派生類的函數(shù)fn2()調(diào)用基類的函數(shù)fn1()調(diào)用基類的函數(shù)fn2()調(diào)用派生類的函數(shù)fn1()調(diào)用派生類的函數(shù)fn2()712 為例91的吹泡泡程序加一版權(quán)（About）對話框。然后修改例91的程序，加入以下內(nèi)容：程 序：1．在程序首部加上文件包含命令 include “”2．在框架窗口類之前加入從CDialog類派生的對話框類：// 對話框類class CAboutDlg: public CDialog { public: CAboutDlg()。enum {IDD = IDD_DIALOG1}。}。inlineCAboutDlg::CAboutDlg():CDialog(CAboutDlg::IDD){} 3．在框架窗口類中添加響應鼠標右鍵消息的代碼，包括消息響應函數(shù)說明、消息響應宏和消息響應函數(shù)定義。鼠標右鍵消息響應函數(shù)為：void CMyWnd::OnRButtonDown(UINT nFlags, CPoint point){ CAboutDlg dlg。()。}713 簽名留念簿程序。該程序模仿簽名簿，用戶使用鼠標左鍵點擊窗口客戶區(qū)后會彈出一個對話框，輸入姓名后可在鼠標點擊位置顯示出該簽名。簽名的顏色、字體大小和方向隨機確定。說 明：項目建立及添加對話框模板資源的方法同例141。修改對話框模板的ID為IDD_NAMEDLG，Caption為“簽名對話框”，并添加一個靜態(tài)文本控件（Caption改為“簽名”）和一個編輯控件（ID改為IDC_EDITNAME）。程 序：// Example 142：簽名留念簿程序 include include ”“ // 對話框類class CNameDlg: public CDialog { public: CPoint m_pointTopLeft。CString m_strNameEdit。public: CNameDlg()。enum {IDD = IDD_NAMEDLG}。protected: virtual void DoDataExchange(CDataExchange* pDX)。virtual BOOL OnInitDialog()。}。// 對話框類的構(gòu)造函數(shù)CNameDlg::CNameDlg():CDialog(CNameDlg::IDD){ m_strNameEdit = _T(”“)。} // 數(shù)據(jù)交換和數(shù)據(jù)檢驗void CNameDlg::DoDataExchange(CDataExchange* pDX){ CDialog::DoDataExchange(pDX)。DDX_Text(pDX, IDC_EDITNAME, m_strNameEdit)。DDV_MaxChars(pDX, m_strNameEdit, 20)。}// 初始化對話框BOOL CNameDlg::OnInitDialog(){CDialog::OnInitDialog()。CRect rect。GetWindowRect(amp。rect)。rect = CRect(m_pointTopLeft, ())。MoveWindow(rect)。return TRUE。}// 簽名類class CSignal: public CObject {CString m_sName。// 姓名CPoint m_pointSignal。// 簽名位置 int m_nHeight。// 字體高 int m_nColor。// 簽名顏色 int m_nEscapement。// 簽名傾角 public: CSignal(){}void SetValue(CString name,CPoint point,int height,int color，int escapement)。void ShowSignal(CDC *pDC)。}。// 簽名類成員函數(shù)void CSignal::SetValue(CString name,CPoint point,int height,int color, int escapement){m_sName = name。m_pointSignal = point。m_nHeight = height。m_nColor = color。m_nEscapement = escapement。}// 顯示簽名void CSignal::ShowSignal(CDC *pDC){CFont *pOldFont, font。(m_nHeight, 0, m_nEscapement,0, 400, FALSE,FALSE，0, OEM_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS,DEFAULT_QUALITY, DEFAULT_PITCH, ”楷體“)。pOldFont = pDCSelectObject(amp。font)。switch(m_nColor){case 0: pDCSetTextColor(RGB(0, 0, 0))。break。case 1: pDCSetTextColor(RGB(255, 0, 0))。break。case 2: pDCSetTextColor(RGB(0, 255, 0))。break。case 3: pDCSetTextColor(RGB(0, 0, 255))。break。} pDCTextOut(, , m_sName)。pDCSelectObject(pOldFont)。} // 框架窗口類 define MAX_NAME 250 class CMyWnd: public CFrameWnd { CSignal m_signalList[MAX_NAME]。int m_nCount。public: CMyWnd(): m_nCount(0){} protected: afx_msg void OnLButtonDown(UINT nFlags, CPoint point)。afx_msg void OnPaint()。DECLARE_MESSAGE_MAP()}。// 消息映射BEGIN_MESSAGE_MAP(CMyWnd, CFrameWnd)ON_WM_LBUTTONDOWN()ON_WM_PAINT()END_MESSAGE_MAP()// 框架窗口類的成員函數(shù) // 鼠標右鍵消息響應函數(shù)void CMyWnd::OnLButtonDown(UINT nFlags, CPoint point){ if(m_nCount MAX_NAME){ CNameDlg dlg。 = point。if(()== IDOK){ int height = rand()%60+12。int color = rand()%4。int escapement =(rand()%1200)600。CString name = 。m_signalList[m_nCount].SetValue(name,point,height, color,escapement)。m_nCount++。Invalidate()。} } }// 繪制框架窗口客戶區(qū)函數(shù) void CMyWnd::OnPaint(){CPaintDC dc(this)。for(int i=0。i// 應用程序類class CM