• 異常類

   1 #pragma once
   2 #include <initializer_list>
   3 using namespace std;
   4 
   5 class memerror
   6 {
   7 };
   8 
   9 class outerror
  10 {
  11 };
  12 
  13 class safeintarray
  14 {
  15 private:
  16     int *p;
  17     int n;
  18 
  19 public:
  20     safeintarray(int length);
  21     safeintarray(initializer_list<int
   
  > mylist);
  22     safeintarray();
  23     int &operator [](int num);
  24     ~safeintarray();
  25 };

•  1 #include "safeintarray.h"
   2 
   3 
   4 
   5 safeintarray::safeintarray(int length)
   6 {
   7     if (length <= 0)
   8     {
   9         throw memerror();
  10     }
  11     this->p = new int[length] {0
   
  };
  12     this->n = length;
  13 }
  14 
  15 safeintarray::safeintarray(initializer_list<int> mylist)
  16 {
  17 }
  18 
  19 safeintarray::safeintarray()
  20 {
  21 }
  22 
  23 int & safeintarray::operator[] (int num)
  24 {
  25     // TODO: 在此處插入 return 語句
  26     if (num<0 || num>this->n - 1)
  27     {
   
  28         throw outerror();
  29     }
  30 
  31     return this->p[num];
  32 }
  33 
  34 
  35 safeintarray::~safeintarray()
  36 {
  37 }

• main.cpp

   1 #include <iostream>
   2 #include "safeintarray.h"
   3 using namespace std;
   4 
   5 void main()
   6 {
   7     try
   8     {
   9         safeintarray s1(5);
  10 
  11         cout << s1[5] << endl;
  12     }
  13     catch(outerror e)
  14     {
  15         cout << "內存分配錯誤" << endl;
  16     }
  17     catch (memerror e)
  18     {
  19         cout << "越界" << endl;
  20     }
  21 
  22     cin.get();
  23 }

134.異常類的處理