我正在尝试使用std::vector<T*>::push_back
and std::mem_fun
,std::binder1st
但这似乎不可行,可以这样做吗?
我试图用下面的代码来举例说明。
#include <vector>
#include <functional>
#include <iostream>
using namespace std;
struct A {
int _Foo;
virtual int AFoo() { return _Foo; };
};
struct B: public A {
int BFoo(int bar) { return _Foo+bar ; };
};
struct C: public A {
int CFoo() { return --_Foo; };
};
class MyContainer
{
static const int MyArraySize = 100;
A* MyArray[MyArraySize];
public:
MyContainer() {
int half = MyArraySize / 2;
for( int i=0; i< half; ++i )
MyArray[i] = new B;
for( int i=half; i < MyArraySize; ++i )
MyArray[i] = new C;
}
template<class T, class Fn1>
int Execute( Fn1 func )
{
int count = 0;
for( int i=0; i< MyArraySize; ++i ){
T* t = dynamic_cast<T*>(MyArray[i]);
if( t )
{
func(t);
++count;
}
}
return count;
}
template<class T, class Res, class Arg>
int Execute( mem_fun1_t<Res, T, Arg> func, Arg argument )
{
return Execute<T>( binder2nd< mem_fun1_t<Res,T,Arg> >( func, argument ) );
}
template<class T>
vector<T*> GetItems() // <-- This is the problem function
{
vector<T*> ret;
Execute<T>( bind1st( mem_fun(&vector<T*>::push_back), ret ) );
return ret;
}
};
int main( int argc, char* argv[] )
{
MyContainer cont;
cont.Execute<B>( mem_fun(&B::BFoo), 10 );
cont.Execute<C>( mem_fun(&C::CFoo) );
vector<B*> v = cont.GetItems<A>(); // <-- the problem function is called here.
cout << "v.size = " << v.size() << endl;
}
我的目标是拥有一个容器类,我可以告诉它执行一个接收选定项目(“A”对象或“A”派生对象)作为参数的函数。但我没有设法使用std::vector::push_pack
它。