table - driven

C++语言: Codee#25728

01 /*
02 table-driven example from <<thinking in cpp>>
03 */
04
05
06 #include <iostream>
07 using namespace std;
08
09 #define DF(N) void N(){\
10     cout << "function"#N " called..."<<endl;}
11
12 DF(a);
13 DF(b);
14 DF(c);
15 DF(d);
16
17 void (*func_table[])() = {a, b, c, d};
18
19 int main()
20 {
21     while(1)
22     {
23         cout << "press a key from 'a' to 'd'\
24         or 'q' to quit" << endl;
25         char c, cr;
26         cin.get(c);
27         cin.get(cr);
28         if(c == 'q')
29             break;
30         if(c < 'a' || c > 'd')
31             continue;
32         (*func_table[c - 'a'])();
33     }
34     return 0;
35 }