1、C+ for the MFE class at UC Berkeley Session #2,Yuli Kaplunovsky MFE, MBA, MS-Tax, CFA yuliFinancialS (408) 884 5965,2,Inheritance: derive one class from another,class Mammal public:Mammal();Mammal();int GetAge();void SetAge(int);int GetWeight();void SetWeight();void Speak();void Sleep();protected:in
2、t itsAge;int itsWeight; ;,enum BREED SHETLAND, DOBERMAN, LAB ;class Dog : public Mammal public:Dog();Dog();BREED GetBreed() const;void SetBreed(BREED);protected:BREED itsBreed; ;,void main() Dog fido;fido.SetAge(3);fido.SetBreed( SHETLAND );cout “Fido is “ fido.GetAge() “ years oldn“; ,3,Inheritance
3、: Overriding Functions,class Mammal public:/ constructorsMammal() cout “Mammal constructor.n“; Mammal() cout “Mammal destructor.n“; void Speak() cout “Mammal sound!n“; void Sleep() cout “shhh. Im sleeping.n“; protected:int itsAge;int itsWeight; ;,class Dog : public Mammal public:Dog() cout “Dog cons
4、tructor.n“; Dog() cout “Dog destructor.n“; void WagTail() cout “Tail wagging.n“; void BegForFood() cout “Begging for food.n“; void Speak() cout “Woof!n“; private:BREED itsBreed; ;,int main() Mammal bigAnimal;Dog fido;bigAnimal.Sleep();bigAnimal.Speak();fido.Sleep();fido.Speak();return 0; Mammal cons
5、tructor. Mammal constructor. Dog constructor. Shh. Im sleeping. Mammal sound! Shh. Im sleeping. Woof! Dog destructor. Mammal destructor. Mammal destructor.,4,Pointer to a class,void PrintDogsAge( Dog * P ) printf(“The age of the ”“Dog is: %d n“, P-GetAge(); ,void main() Dog *pFido = new Dog;pFido-Se
6、tAge( 4 );PrintDogsAge( pFido );Dog *pMyDog;pMyDog = pFido;PrintDogsAge( pMyDog );Dog Barky;Barky.SetAge(3);pMyDog = ,Exercise: Write the output of this program,5,Virtual,class Mammal public:Mammal():itsAge(1) cout “Mammal constructor.n“; Mammal() cout “Mammal destructor.n“; void Move() cout “Mammal
7、 move one stepn“; virtual void Speak() cout “Mammal speak!n“; protected:int itsAge; ;,class Dog : public Mammal public:Dog() cout “Dog Constructor.n“; Dog() cout “Dog destructor.n“; void WagTail() cout “Wagging Tail.n“; void Speak() cout “Woof!n“; void Move() cout “Dog moves 5 steps.n“; ;,int main()
8、 Mammal *pDog = new Dog;pDog-Move();pDog-Speak(); Mammal constructor. Dog Constructor. Mammal move one step Woof!,Dog Fido;Fido.Move();Fido.Speak();Mammal constructor. Dog Constructor. Dog moves 5 steps Woof! Dog destructor Mammal destructor,6,Virtual Why do we need it?,For example, you could create
9、 many different types of windows, including dialog boxes, scrollable windows, and list boxes, and give them each a virtual draw() method. By creating a pointer to a window and assigning dialog boxes and other derived types to that pointer, you can call draw() without regard to the actual run-time ty
10、pe of the object pointed to. The correct draw() function will be called.,Exercise: Write example of three classes: base class (CWindow), and two derivative classes (CListBox and CDialogBox) which implement the function draw differently. And a function that receives a pointer of the type CWindow, and
11、 calls the draw function.,7,Static variables,class Cat public:Cat(int age):itsAge(age) HowManyCats+; virtual Cat() HowManyCats-; virtual int GetAge() return itsAge; virtual void SetAge(int age) itsAge = age; static int HowManyCats;private:int itsAge; ;,int Cat:HowManyCats = 0; void main() const int
12、MaxCats = 5; int i;Cat *CatHouseMaxCats;for (i = 0; iGetAge() “ years oldn“;delete CatHousei;CatHousei = 0; ,There are 5 cats left! Deleting the one which is 0 years old There are 4 cats left! Deleting the one which is 1 years old There are 3 cats left! Deleting the one which is 2 years old There ar
13、e 2 cats left! Deleting the one which is 3 years old There are 1 cats left! Deleting the one which is 4 years old,8,Static Function simple,class Cat public: static int GetNumberOfCats() return HowManyCats; static int HowManyCats;private:int itsAge; ;,int Cat:HowManyCats = 4; void main() int I = Cat:
14、GetNumberOfCats(); ,9,Static Function very complicated,class CBuf public:int A;void CloseCompresBuf();static void StaticCloseCompresBuf( void *B ) (CBuf *)B)-CloseCompresBuf(); ;void CBuf:CloseCompressedBuf() printf(“A = %dn“, A ); ,typedef *FUNC(void *); FUNC *gFunc; void *gParam;void Set_Timer_Tim
15、eout( FUNC Func, void *Param ) gFunc = Func;gParam = Param; void Timer_timeout() gFunc( gParam ); ,void main() CBuf *Buf1 = new CBuf;Buf1-A = 11;Set_Timer_Timeout( (FUNC *) CBuf:StaticCloseCompresBuf, Buf1 );Timer_timeout(); / emulate interrupt ,10,Next week:,More examples MFC classes CString etc Wr
16、iting Windows application using CDialog,Exercise / Homework: This was the basic foundation of C+ Spending ONLY 2.5 hours in class is NOT enough to master the foundation The easiest way to memorize it and get more familiar with it is to surprisingly simple - COPY all the samples and run them one by o
17、ne on your PC.And based on this foundation,11,MFC Microsoft Foundation Classes,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,class CAboutDlg : public CDialog public:CAboutDlg();enum IDD = IDD_ABOUTBOX ; / Dialog Data protected:virtual void DoDataExchange(CDataExchange* pDX); / DDX/DDV support / Imple
18、mentation protected:DECLARE_MESSAGE_MAP() ;CAboutDlg:CAboutDlg() : CDialog(CAboutDlg:IDD) void CAboutDlg:DoDataExchange(CDataExchange* pDX) CDialog:DoDataExchange(pDX); BEGIN_MESSAGE_MAP(CAboutDlg, CDialog) END_MESSAGE_MAP(),Implementing CDialog,27,void Capp1Dlg:OnSysCommand(UINT nID, LPARAM lParam)
19、 if (nID ,28,Next week:,More examples More MFC classes CFile etc Windows application - Part 2,Exercise / Homework: This was the basic foundation of C+ Spending ONLY 2.5 hours in class is NOT enough to master the foundation The easiest way to memorize it and get more familiar with it is to surprisingly simple - COPY all the samples and run them one by one on your PC.And based on this foundation,
