aCC下的fstream

发布: 2007-6-08 22:43 | 作者: seanhe | 来源: | 查看: 31次 | 进入软件测试论坛讨论

使用stl,就意味着告别熟悉的c-style编程方式,对文件的处理也毫不例外.

fstream可以用来对文件进行处理,它象对待数据流一样对待文件.

以下给出一个例子.关键是事先要创建fstream.out文件,哪怕是个空文件,也要先创建.因为fstream不会为你创建.

#include<iostream>
#include<fstream>
int main ( )
{
using namespace std;

// create a bi-directional fstream object
fstream inout("fstream.out");

          // output characters
         inout << "Das ist die rede von einem man" << endl;
         inout << "C'est l'histoire d'un home" << endl;
         inout << "This is the story of a man" << endl;

char p[100];

// seek back to the beginning of the file
inout.seekg(0);

// extract the first line
inout.getline(p,100);

          // output the first line to stdout
         cout << endl << "Deutch :" << endl;
         cout << p;

fstream::pos_type pos = inout.tellg();

// extract the second line
inout.getline(p,100);

          // output the second line to stdout
         cout << endl << "Francais :" << endl;
         cout << p;

// extract the third line
inout.getline(p,100);

          // output the third line to stdout
         cout << endl << "English :" << endl;
         cout << p;

// move the put sequence before the second line
inout.seekp(pos);

// replace the second line
inout << "This is the story of a man" << endl;

          // replace the third line
         inout << "C'est l'histoire d'un home";
          // replace the third line
         inout << "C'est l'histoire d'un home";

// seek to the beginning of the file
inout.seekg(0);

          // output the all content of the fstream
          // object to stdout
         cout << endl << endl << inout.rdbuf();
}