Re: how to separate a class code to different files?

Hi all
I wrote:

#include <cstdlib>
#include <iostream>
#include <string>
using namespace std;

class BaseNode
{
public:
 void return_message(string );
};

void BaseNode::return_message(string str)
{
std::cout << str;
}

int main(int argc, char *argv[])
{
   string a = "dasdasd";
   BaseNode test;
   test.return_message(a);

   system("PAUSE");
   return EXIT_SUCCESS;
}

// ok this can pass compile but when I want to separated code to .h
files:
//******************* main.cpp
#include <cstdlib>
#include <iostream>
#include <string>

using namespace std;

#include "BaseNode.h

int main(int argc, char *argv[])
{
   string a = "dasdasd";
   BaseNode test;
   test.return_message(a);

   system("PAUSE");
   return EXIT_SUCCESS;
}

//******************* basenode.h
#ifndef BASENODE_H_
#define BASENODE_H_

class BaseNode
{
public:
 void return_message(string );
};

#endif //BASENODE_H_

//******************* basenode.cpp

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

void BaseNode::return_message(string str)
{
std::cout << str;
}

//this can not pass compile : 5 D:\a\testclass\BaseNode.cpp `BaseNode' has
not been declared

this confuse exist on my other post on compile ,cause undefined reference
to foo::foo() but when I move foo's implement to .h file , error gone.

so how to organize a class's .h and .cpp file?