Sams Teach Yourself C++ in 21 Days

22:

23: void OutOfMemory::PrintError()

24: {

25: cout << “Out of Memory!!” << endl;

26: }

27:

28: // Derived class to handle bad numbers

29: class RangeError : public Exception

30: {

31: public:

32: RangeError(unsigned long number){badNumber = number;}

33: ~RangeError(){}

34: virtual void PrintError();

35: virtual unsigned long GetNumber() { return badNumber; }

36: virtual void SetNumber(unsigned long number) {badNumber =

➥number;}

37: private:

38: unsigned long badNumber;

39: };

40:

41: void RangeError::PrintError()

42: {

43: cout << “Number out of range. You used “ ;

44: cout << GetNumber() << “!!” << endl;

45: }

46:

47: void MyFunction(); // func. prototype

48:

49: int main()

50: {

51: try

52: {

53: MyFunction();

54: }

55: // Only one catch required, use virtual functions to do the

56: // right thing.

57: catch (Exception& theException)

58: {

59: theException.PrintError();

60: }

61: return 0;

62: }

63:

64: void MyFunction()

65: {

66: unsigned int *myInt = new unsigned int;

67: long testNumber;

68:

69: if (myInt == 0)

70: throw OutOfMemory();

71:

870 Appendix D

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