看看CFile的使用

   
     

    
       1 
    
      /*
    
      该函数用来将文件中所有的大写字母转化为小写字母，但是不支持UNICODE
    
      */
    
      

    
       2 
    
      #include 
    
      <
    
      afx.h
    
      >
    
      

    
       3 
    
      
    
      //
    
      #include <iostream>

    
       4 
    
      
    
      //
    
      using namespace::std;
    
      

    
       5 
    
      
    
      

    
       6 
    
      
    
      int
    
       main()

    
       7 
    
      {

    
       8 
    
       BYTE buffer[
    
      0x100
    
      ];

    
       9 
    
       
    
      try
    
      

    
      10 
    
       {

    
      11 
    
       CFile file(L
    
      "
    
      File2.txt
    
      "
    
      , CFile::modeReadWrite);

    
      12 
    
       ULONGLONG dwBytesRemaining 
    
      =
    
       file.GetLength();

    
      13 
    
       
    
      while
    
      (dwBytesRemaining)

    
      14 
    
       {

    
      15 
    
       ULONGLONG dwPosition 
    
      =
    
       file.GetPosition();

    
      16 
    
       UINT nBytesRead 
    
      =
    
       file.Read(buffer,
    
      sizeof
    
      (buffer));

    
      17 
    
       ::CharLowerBuff((LPWSTR)buffer,nBytesRead);

    
      18 
    
       file.Seek(dwPosition,CFile::begin);

    
      19 
    
       file.Write(buffer,nBytesRead);

    
      20 
    
       dwBytesRemaining 
    
      -=
    
       nBytesRead;

    
      21 
    
       }

    
      22 
    
       file.Close(); 

    
      23 
    
       }

    
      24 
    
       
    
      catch
    
      (CFileException 
    
      *
    
      e)

    
      25 
    
       {

    
      26 
    
       
    
      //
    
      cout<<"Third: Failed!"<<endl;
    
      

    
      27 
    
      
    
       e
    
      ->
    
      ReportError();

    
      28 
    
       e
    
      ->
    
      Delete();

    
      29 
    
       }

    
      30 
    
      

    
      31 
    
       
    
      return
    
       
    
      0
    
      ;

    
      32 
    
      }
   
     

  
    

   
     /*本人闲暇之余学习MFC的CFile类，在学习的过程中，写了如下的程序进行练习，贴出来和大家共享, Enjoy it.
 ------cylee
*/
 1 
   
     #include 
   
     <
   
     afx.h
   
     >
   
     

   
      2 
   
     #include 
   
     <
   
     iostream
   
     >
   
     

   
      3 
   
     
   
     using
   
      
   
     namespace
   
     ::std;

   
      4 
   
     

   
      5 
   
     
   
     int
   
      main()

   
      6 
   
     {

   
      7 
   
      CFile file;

   
      8 
   
      CFileException err;

   
      9 
   
     

   
     10 
   
     

   
     11 
   
      
   
     //
   
     The following code try to open a file named File.txt,

   
     12 
   
      
   
     //
   
     It will fail unless the file is located in the the current directoty,

   
     13 
   
      
   
     //
   
     because the Open member function open files only.

   
     14 
   
      
   
     //
   
     The open member function doesn't throw any exception, so you can

   
     15 
   
      
   
     //
   
      not use try-catch mechanism to catch errors, but you can do it in another way.
   
     

   
     16 
   
     
   
     

   
     17 
   
      
   
     if
   
     ( file.Open(_T(
   
     "
   
     File.txt
   
     "
   
     ),CFile::modeReadWrite,
   
     &
   
     err))

   
     18 
   
      cout
   
     <<
   
     "
   
     First: Succeeded!
   
     "
   
     <<
   
     endl;

   
     19 
   
      
   
     else
   
     

   
     20 
   
      err.ReportError();

   
     21 
   
      file.Close();

   
     22 
   
     

   
     23 
   
      
   
     //
   
     Use constructor to open a file without creation, too.

   
     24 
   
      
   
     //
   
     an exception is throwed when an error accured.
   
     

   
     25 
   
     
   
      
   
     try
   
     

   
     26 
   
      {

   
     27 
   
      CFile file2(_T(
   
     "
   
     File.txt
   
     "
   
     ), CFile::modeReadWrite);

   
     28 
   
      cout
   
     <<
   
     "
   
     Second: Succeeded!
   
     "
   
     <<
   
     endl;

   
     29 
   
      }

   
     30 
   
      
   
     catch
   
     (CFileException 
   
     *
   
     e)

   
     31 
   
      {

   
     32 
   
      cout
   
     <<
   
     "
   
     Second: Failed!
   
     "
   
     <<
   
     endl;

   
     33 
   
      e
   
     ->
   
     ReportError();

   
     34 
   
      e
   
     ->
   
     Delete();

   
     35 
   
      }

   
     36 
   
     

   
     37 
   
      
   
     //
   
     Create and Open a file in only one statement.
   
     

   
     38 
   
     
   
     }