实验七文件的输入输出

1~2

#include<iostream>
#include<fstream>
#include<string.h>
using namespace std;
typedef struct { string name,num;
      double Buy,Sell,Deal;
        }Node;
Node node[4];
int main()
{     //输出该编译器的文件。 
    /*ifstream fin("D:\\编程文件\\main.cpp",ios_base::in);
    if(fin)
    { char ch;
      while((ch=fin.get())!=EOF)
         cout.put(ch);
    }
    fin.close();
     */
    ofstream file("c:\\stock.dat",ios_base::out|ios_base::binary);
    if(!file) 
    cerr<<"open error!!!"<<endl,abort(); //结束程序 
    for(int i=0;i<4;++i)
    {cin>>node[i].name>>node[i].num>>node[i].Buy>>node[i].Sell>>node[i].Deal;
     file.write(reinterpret_cast<char*>(&node[i]),sizeof(node[i]));
    }
    file.close();
    ifstream f("c:\\stock.dat",ios_base::in|ios_base::binary);
    while(!f.eof())//判断是不是到文件的结尾
    { Node s;
   f.read(reinterpret_cast<char*>(&s),sizeof(s));
   cout<<s.name<<" "<<s.num<<" "<<s.Buy<<" "<<s.Sell<<" "<<s.Deal<<endl;
   }
   f.close();
   system("pause");
   return 0;
} 

3，，这个实验做的有点纠结，，，，，，，，

#include<iostream>
#include<fstream>
#include<string.h>
using namespace std;
ofstream file;
class MailMan
{public:
    bool bHaveMsg ; //是否有信息的标记
    void OutMsg(); //显示用户输入的信息
    void ReadMsgFromFile(); //从文件中读取信息
    void SaveMsgToFile(); //向文件中保存信息
    void InMsg(); //接收用户的信息
    MailMan();
    virtual ~MailMan() {}
private:
   char  Buf[1024];
    fstream fs ;
};
MailMan::MailMan()
{   memset(Buf,'\0',sizeof(Buf));
 fs.open("C:\\msg.ini",ios_base::in|ios_base::binary);
  fs.close();
  bHaveMsg=false;
}
void MailMan::SaveMsgToFile()
{ file.open("C:\\msg.ini",ios_base::app|ios_base::binary);
  file.write(reinterpret_cast<char*>(&Buf),sizeof(Buf));
  file.close();
  bHaveMsg=true;
}
void MailMan::InMsg()
{ cin>>Buf;
 cout<<endl;
 }
void MailMan:: ReadMsgFromFile()
{   fs.open("C:\\msg.ini",ios_base::in|ios_base::binary);
    char ch;
   /*while((ch=fs.get())!=EOF)
   cout.put(ch);
   cout<<endl;
   fs.close();
   */
   
   while(!fs.eof())
   {  while((ch=fs.get())!=EOF)
       cout.put(ch);
   }
    fs.close();
   
    
}
void MailMan::OutMsg()
{   ReadMsgFromFile();
    InMsg();
   SaveMsgToFile();
}
int main()
{  file.open("C:\\msg.ini",ios_base::app|ios_base::binary);
    char ch[100];
    cin>>ch;
   file.write(reinterpret_cast<char*>(&ch),sizeof(ch));
   file.close();
    MailMan a;
    a.OutMsg();
    a.OutMsg();
    system("pause");
}