//类定义 stringbad.h
#include<iostream>
using namespace std;
#ifndef stringbad_H_
#define stringbad_H_
class stringbad
{
private:
 char *str;
 int len;
 static int num_strings;
public:
 stringbad();
 stringbad(const char *s);
 ~stringbad();
 //friend function
 friend ostream &operator<<(ostream &os,const ostream &st);
};
#endif
//类方法 stingbad.cpp
#include<iostream>
#include<cstring>
#include"stringbad"
using namespace std;
int stringbad::num_strings=0;//初始华静态数
stringbad::stringbad()
{
 len=4;
 str=new char[4];
 strcpy(str,"C++");
 num_strings++;
 cout<<num_stirngs<<":\"<<str<<"defaultt object created";
}
stringbad::stringbad(const char *s)
{
 len=strlen(s);
 str=new char[len+1];
 strcpy(str,s);
 num_strings++;
 cout<<num_strings<<":\"<<str<<"object created"<<endl;
}
stringbad::~stringbad()
{
 cout<<"\"<<str<<"\"object delete"<<endl;
    --num_strings;
 cout<<num_strings<<"left\n";
 delete [] str;
 
}
ostream &operator<<(ostream &os,const stringbad & st)
{
 os<<st.str;
 return os;
}
//主函数
#include<iostream>
#include"stringbad.h"
using namespace std;
//void callme1(stringbad &);
//void callme2(stringbad);
int main()
{
 stringbad headline1("Celery Stalks at Midnight");//创建一个headline1对象
 stringbad headline2("lettuce Prey");
 stringbad sports("Spinach Leaves Bow1 for Dollars");
 cout<<"headline1"<<headline1<<endl;
 cout<<"headline2"<<headline2<<endl;
 cout<<"sprots"<<sports;
 return 0;
}

类方法 stingbad.cpp中
#include"stringbad"   改为  #include"stringbad.h" 试试

你用的是什么编译器，vc6有个BUG，包含<iostream>之后，你重载<< or >>时编译不通过，用<iostream.h>就没事