Re: reading string from a text file from vc++ without MFC support

From:
MrAsm <mrasm@usa.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Sun, 17 Jun 2007 09:43:32 GMT
Message-ID:
<950a731m60h7gmgdbnf3ga820pqduu4e2d@4ax.com>
On Sat, 16 Jun 2007 23:11:11 -0700, rindam2002@yahoo.com wrote:

will U plz get me a code for reading file line by
line using FILE structure.


OK, I understand that you want to use C 'FILE *'.

my text file will be having random number of
data such as
      atlanta/123
      atlanta/greetings
      atlanta/double
      ............
      ............
      ....//random nuber of lines.
Now I need to read each line of the file and save it into a string
variable and use this variable in the application.the problem here is


The problem is easy. You just need to open the file using _tfopen
(_tfopen is the Unicode-aware version of standard C fopen), read text
lines using _fgetts (the Unicode-aware version of standard C fgets),
until you reach end of file (use feof to test it) and close the file
with fclose.

You read each file line into a temporary local buffer (TCHAR array of
maximum specified size) using _fgetts, and then you can store the line
you have just read in the old-style C buffer into a more modern robust
useful CString instance.

<CODE>
    CString fileName = _T("c:\\prova.txt");

    // Open the file for reading in text mode
    FILE * file = _tfopen( fileName, _T("rt"));
    // If file == NULL ... error

    // Maximum number of characters in a line
    static const int maxLineChars = 200;

    // This will store each line of text
    TCHAR line[ maxLineChars ];

    // Read line by line from file
    while ( ! feof(file) )
    {
        // Clear destination buffer
        ::ZeroMemory( line, sizeof(line) );

        // Read the line
        _fgetts( line, maxLineChars, file );

        // Now 'line' contains the line read from file.
        // Do your processing.
        // e.g.: You may store the read line into a CString
        CString strLine( line );

        // Process strLine...
        // DoLineProcessing( strLine );
        ...
    }

    // Close the file
    fclose(file);
    file = NULL; // Avoid dangling references

</CODE>

that I dont know How many lines will the file have.


No problem: 'feof' function and 'while' statement help you here :)

MrAsm

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