C ++映射字符串和成员函数指针 [英] C++ Map of string and member function pointer

问题描述

嘿，所以我做一个地图用字符串作为键和一个成员函数指针作为值。我似乎无法弄清楚如何添加到地图中，这似乎不起作用。

Hey so I am making a map with string as the key and a member function pointer as the value. I can't seem to figure out how to add to the map, this doesn't seem to be working.

#include <iostream>
#include <map>
using namespace std;

typedef string(Test::*myFunc)(string);
typedef map<string, myFunc> MyMap;


class Test
{
private:
    MyMap myMap;

public:
    Test(void);
    string TestFunc(string input);
};





#include "Test.h"

Test::Test(void)
{
    myMap.insert("test", &TestFunc);
    myMap["test"] = &TestFunc;
}

string Test::TestFunc(string input)
{
}

推荐答案

请参阅 std :: map :: insert 和 value_type

myMap.insert(std::map<std::string, myFunc>::value_type("test", &Test::TestFunc));

和 operator []

myMap["test"] = &Test::TestFunc;

不能使用没有对象的成员函数的指针。您可以使用指向成员函数的指针，其类型为 Test对象

You cannot use a pointer to member function without an object. You can use the pointer to member function with an object of type Test

Test t;
myFunc f = myMap["test"];
std::string s = (t.*f)("Hello, world!");

或指向的指针测试 / p>

or with a pointer to type Test

Test *p = new Test();
myFunc f = myMap["test"];
std::string s = (p->*f)("Hello, world!");

另请参见 C ++常见问题 - 指向成员函数的指针

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