利用C++重载实现类似“类成员指针”的功能
代码如下：
//: PointerToMemberOperator.cpp
#include <iostream>
using namespace std;
class Dog
{
public:
int run(int i) const
{
cout << "run\n";
return i;
}
int eat(int i) const
{
cout << "eat\n";
return i;
}
int sleep(int i) const
{
cout << "ZZZ\n";
return i;
}
typedef int (Dog::*PMF)(int) const;
// operator->* must return an object
// that has an operator():
class FunctionObject
{
Dog* ptr;
PMF pmem;
public:
// Save the object pointer and member pointer
FunctionObject(Dog* wp, PMF pmf)
: ptr(wp), pmem(pmf)
{
cout << "FunctionObject constructor\n";
}
// Make the call using the object pointer
// and member pointer
int operator()(int i) const
{
cout << "FunctionObject::operator()\n";
return (ptr->*pmem)(i); // Make the call
}
};
FunctionObject operator->*(PMF pmf)
{
cout << "operator->*" << endl;
return FunctionObject(this, pmf);
}
};
int main() {
Dog w;
Dog::PMF pmf = &Dog::run;
cout << (w->*pmf)(1) << endl;
pmf = &Dog::sleep;
cout << (w->*pmf)(2) << endl;
pmf = &Dog::eat;
cout << (w->*pmf)(3) << endl;
}
摘自yucan1001
补充：软件开发 , C++ ,
