/* 范例：11-7 */
#include <fstream.h>
void main()
{
  ofstream out_file("out.txt"); 	// # 1 if(變更out.txt屬性只讀,隱藏)

  out_file << "My name is Peipei.\n";
  out_file.put('B').put('o').put('y'); 	// # 2如同cout.put(ch)...
  cout << "out_file.is_open()=" << out_file.is_open() << endl;
  out_file.close();	// # 3

  ifstream in_file("out.txt");	// # 4  if(變更為不存在文件,out1.txt)
  cout << "in_file.is_open()=" << in_file.is_open() << endl;	// # 5
  cout << "in_file.fail()=" << in_file.fail() << endl;        	// # 6
  cout << in_file.rdbuf();	// # 7
  in_file.close();	// # 8
  getchar();
}

程序執(zhí)行結(jié)果：(依 #1、#4 設(shè)定而不同，兩者皆成功時(shí)，結(jié)果如下)
out_file.is_open()=1
in_file.is_open()=1
in_file.fail()=0
My name is Peipei.
Boy