可能重复:
Function with same name but different signature in derived class
我正在尝试编译这个,我无法弄清楚代码有什么问题。我正在使用MacOSX Snow Leopard和Xcode g ++版本4.2.1。有人能告诉我这是什么问题吗?我认为这应该编译。这不是我的作业,我是一名开发人员......至少我以为自己被这个问题困住了。我收到以下错误消息:
error: no matching function for call to ‘Child::func(std::string&)’
note: candidates are: virtual void Child::func()
以下是代码:
#include <string>
using namespace std;
class Parent
{
public:
Parent(){}
virtual ~Parent(){}
void set(string s){this->str = s;}
virtual void func(){cout << "Parent::func(" << this->str << ")" << endl;}
virtual void func(string& s){this->str = s; this->func();}
protected:
string str;
};
class Child : public Parent
{
public:
Child():Parent(){}
virtual ~Child(){}
virtual void func(){cout << "Child::func(" << this->str << ")" << endl;}
};
class GrandChild : public Child
{
public:
GrandChild():Child(){}
virtual ~GrandChild(){}
virtual void func(){cout << "GrandChild::func(" << this->str << ")" << endl;}
};
int main(int argc, char* argv[])
{
string a = "a";
string b = "b";
Child o;
o.set(a);
o.func();
o.func(b);
return 0;
}
答案 0 :(得分:11)
Child::func()
的{{1}}隐藏了<{1}}的所有重载,包括Parent::func
。你需要一个“使用”指令:
Parent::func(string&)
编辑: 或者,您可以自己指定正确的范围:
class Child : public Parent
{
public:
using Parent::func;
Child():Parent(){}
virtual ~Child(){}
virtual void func(){cout << "Child::func(" << this->str << ")" << endl;}
};