c++ - 指向基类错误的成员函数的指针

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7年前关闭。




有人可以帮我确定我要去哪里错吗？我正在尝试使用指向基类函数的函数指针

错误C2064:术语不等于行号30上带有0个参数的函数的值，即*(app)()

#include<stdio.h>
#include<conio.h>
#include<stdarg.h>
#include<typeinfo>

using namespace std;

class A{
public:
    int a(){
        printf("A");
        return 0;
    }
};

class B : public A{
public:
    int b(){
        printf("B");
        return 0;
    }
};

class C : public B{
public:
    int(C::*app)();
    int c(){
        app =&C::a;
        printf("%s",typeid(app).name());
        *(app)();
        printf("C");
        return 0;
    }
};
int main(){
    C *obj = new C();
    obj->c();
    getch();
}

最佳答案

在调用指向成员函数的指针时，必须使用。*或-> *

    class C : public B{
    public:
        int(C::*app)();
        int c(){
            app =&C::a;
            printf("%s",typeid(app).name());
            (this->*app)(); // use ->* operator within ()
            printf("C");
            return 0;
        }
    };

关于c++ - 指向基类错误的成员函数的指针，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/15804586/