boost的Any库学习

http://www.stlchina.org/twiki/bin/view.pl/Main/BoostSource_any  ppLiu写的关于这个的文章

下面是实例代码

1.

int main()
{
    boost::any a;
    a = std::string("aaaa");

    try
    {
        int val = boost::any_cast<int>(a);
        std::cout<<val<<std::endl;
    }
    catch(boost::bad_any_cast& b)
    {
        std::cout<<"error!"<<std::endl;
    }
   
}

2.

#include <iostream>
#include <string>
#include <utility>
#include <vector>
#include <boost/any.hpp>

class A
{
public:
    void some_function() {std::cout<<"A::some_function()"<<std::endl;}
};

class B
{
public:
    void some_function() {std::cout<<"B::some_function()"<<std::endl;}   
};

class C
{
public:
    void some_function() {std::cout<<"C::some_function()"<<std::endl;}
};

void print_any(boost::any& a)
{
    if(A* pA = boost::any_cast<A>(&a))
    {
        pA->some_function();
    }
   
    else if(B* pB = boost::any_cast<B>(&a))
    {
        pB->some_function();
    }
   
    else if(C* pC = boost::any_cast<C>(&a))
    {
        pC->some_function();
    }
   
    else
    {
        try
        {
            std::cout<<boost::any_cast<std::string>(a)<<std::endl;
        }
        catch(boost::bad_any_cast& b)
        {
            std::cout<<"Oops!"<<std::endl;
        }
    }

}

int main()
{
    std::vector<boost::any> store_anything;
    store_anything.push_back(A());
    store_anything.push_back(B());
    store_anything.push_back(C());
    store_anything.push_back(std::string("love"));
    store_anything.push_back(3);
    store_anything.push_back(std::make_pair(true, 7.92));

    std::for_each(store_anything.begin(), store_anything.end(), print_any);
}

3.