结构体的处理（以c++primer plus 第六章习题4为例）

 1 const unsigned int strsize = 50;
 2 struct bop     //结构体就像一个数据类型如int  使用前应该先给他一个变量如本题中的bop
 3 {
 4     char fullname[strsize];     // real name
 5     char title[strsize];        // job title
 6     char bopname[strsize];      // secret BOP name
 7     int preference;             // 0 = fullname, 1 = title, 2 = bopname
 8 };
 9 void display_by_name(const struct bop *bopArray, unsigned int size)  //const 最小授权  结构体不会被改变     boparray还是一个数组   数组在传递的时候  一般用地址传递  就是指针传递     传递数组时要带上它的数组规模 
10 {
11     for (size_t i = 0; i < size; i++)
12     {
13         cout << bopArray[i].fullname << endl;        //调用结构体中成员的方式
14     }
15 }
16 void display_by_title(const struct bop *bopArray, unsigned int size)
17 {
18     for (size_t i = 0; i < size; i++)
19     {
20         cout << bopArray[i].title << endl;
21     }
22 }
23 void display_by_bopname(const struct bop *bopArray, unsigned int size)
24 {
25     for (size_t i = 0; i < size; i++)
26     {
27         cout << bopArray[i].bopname << endl;
28     }
29 }
30 void display_by_preference(const struct bop *bopArray, unsigned int size)
31 {
32     for (size_t i = 0; i < size; i++)
33     {
34         if (bopArray[i].preference == 0)
35         {
36             cout << bopArray[i].fullname << endl;
37         }
38         else if (bopArray[i].preference == 1)
39         {
40             cout << bopArray[i].title << endl;
41         }
42         else if (bopArray[i].preference == 2)
43         {
44             cout << bopArray[i].bopname << endl;
45         }
46     }
47 }
48 void p6_4(void)
49 {
50     const struct bop bopArray[5] = {                             //给结构体变量初始化的方式
51         {"Wimp Macho", "YYY", "Y----", 0},
52         {"XXXXXXXX", "2XXXX", "3XXXXX", 1},
53         {"AAAAAAAA", "2AAAA", "3AAAAA", 2},
54         {"BBBBBBBB", "2BBBB", "3BBBBB", 0},
55         {"CCCCCCCC", "4CCCC", "3CCCCC", 1}
56     };
57     char choice = 0;
58 
59     cout << "Benevolent Order of Proframers Report" << endl;
60     cout << left << setw(30) << "a. display by name" << "b. display by title" << endl;
61     cout << left << setw(30) << "c. display by bopname" << "d. display by preference" << endl;
62     cout << left << setw(30) << "q. quit" << endl;
63     cout << "Enter your choice:";
64 
65     while (cin >> choice)
66     {
67         if (choice == ‘q‘)
68         {
69             break;
70         }
71         switch (choice)
72         {
73         case ‘a‘:
74             display_by_name(bopArray, 5);
75             break;
76 
77         case ‘b‘:
78             display_by_title(bopArray, 5);
79             break;
80 
81         case ‘c‘:
82             display_by_bopname(bopArray, 5);
83             break;
84 
85         case ‘d‘:
86             display_by_preference(bopArray, 5);
87             break;
88 
89         default:
90             break;
91         }
92         cout << "Next choice:";
93     }
94     cout << "Bye!" << endl;
95     return;
96 }