TICPP CHAPTER 11 EX 27 & EX28

/*
27. Start with FunctionTable.cpp from Chapter 3. Create a
class that contains a vector of pointers to functions, with
add( ) and remove( ) member functions to add and
remove pointers to functions. Add a run( ) function that
moves through the vector and calls all of the functions.
*/
//: C03:FunctionTable.cpp
#include <iostream>
#include <vector>
using namespace std;

// A macro to define dummy functions:
#define DF(N) void N() { /
cout << "function " #N " called..." << endl; }

DF(a); DF(b); DF(c); DF(d); DF(e); DF(f); DF(g);

class FuncTable {
vector<void(*)()>ft;
public:
void add(void(*f)()) {
ft.push_back(f);
}
void remove(){
ft.pop_back();
}
void run() {
for (int i = 0; i < ft.size(); i++) {
//看清楚调用格式 ,有无*号都可以
(*ft[i])();
}
}
};

//void (*func_table[])() = { a, b, c, d, e, f, g };

int main() {
FuncTable test;
test.add(&a);
test.add(&b);
test.run();
test.remove();
cout << "after b() is removed" << endl;
test.run();
} ///:~

//28. Modify the above Exercise 27 so that it works with
//pointers to member functions instead.

//: C03:FunctionTable.cpp
#include <iostream>
#include <vector>
using namespace std;

// A macro to define dummy functions:

#define DF(N) void N() { /
cout << "function X::" #N " called..." << endl; }

#define MAKEX /
class X{ /
public: /
DF(a); DF(b); DF(c); DF(d); DF(e); DF(f); DF(g); /
}

//定义了一个X类
MAKEX;

class FuncTable {
vector<void(X::*)()>ft;
public:
void add(void(X::*f)()) {
ft.push_back(f);
}
void remove(){
ft.pop_back();
}
void run(X& x) { //需要传入一个X类对象，否则无法调用
for (int i = 0; i < ft.size(); i++) {
//看清楚调用格式 ,必须有*号
(x.*ft[i])();
}
}
};

//void (*func_table[])() = { a, b, c, d, e, f, g };

int main() {
X x;
FuncTable test;
test.add(&X::a);
test.add(&X::b);
test.run(x);
test.remove();
cout << "after X::b() is removed." << endl;
test.run(x);
} ///:~