Question

CFile Read using MFC

Asked by: SarwanGul

Hello!
I have a file on hard disk and file has 2 numbers separated by "," .I want to read the numbers from the file using CFile and store the numbers in  2 different int variables.
I am not able to read the numbers from file.Please can u help me out in doing this work.I am pasting my code here.
Regards.

// Multiply.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "Multiply.h"
#include <iostream>;
using namespace std;

Multiply::Multiply()
{
      
      CFile file2;
               
               CString str;
              CString buff;



TCHAR* pBuff;
str=file2.Open("c:\\def.txt", CFile::modeRead);
      

int len = file2.GetLength();

pBuff=buff.GetBuffer(len+1);


str=file2.Read(pBuff, len);
 

buff=str;
file2.Close();
pBuff[len]='\0';
buff.ReleaseBuffer();

pBuff=NULL;

file1.Close();

cout<<str;
}
void main()
{
Multiply mul;
}






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Asked On
2004-04-16 at 11:47:16ID20956914
Tags

cfile

,

read

,

mfc

Topic

Windows MFC Programming

Participating Experts
3
Points
500
Comments
6

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Answers

 

by: AlexFMPosted on 2004-04-16 at 12:02:35ID: 10845183

Use CStdioFile class and CStdioFile::ReadString function:

BOOL ReadString(CString& rString);

Having CString variable use sscanf to read two int variables from it.

 

by: leflonPosted on 2004-04-16 at 12:05:54ID: 10845202

Hi SarwanGul,

your code looks a little weird right now.
let me see if i got your problem right.

you have a file (say 'def.txt') which consits of two numbers seperated by a ','.

[def.txt]
123,456
or
[def.txt]
12.34,56.78

you like to read this numbers and store them to two variables (lets say two double vars).

is this correct??

if so
you should
- open the file for reading (you did this, but the return value of Open func is not a CString but a BOOL telling you if the open was successful)
- read the line to a string(you have to decide if you like to use MFC obejcts and functions -CFile, CString etc.- or the C++ specific string and iostream rountines)
- split the string and assign numbers to values

need any help with this??

leflon

 

by: dxdat99Posted on 2004-04-16 at 20:27:07ID: 10847625

Hi!
U can use this code

----------
    CFile   pfile;
    CString str;
    CString buff;
    long    lNum1 = 0;
    long    lNum2 = 0;
    TCHAR *tcData;
    if(!pfile.Open("d:\\Text.txt", CFile::modeRead))
    {
        return;
    }
    int len = pfile.GetLength();      
    tcData = new TCHAR[len + 1];
    tcData[len] = '\0';
    pfile.Read(tcData, len);
    CString szBuff(tcData);
    int pos = szBuff.Find(_T(","));
    if(pos > 0)  // if found ',' character
    {
        lNum1 = _ttol(szBuff.Left(pos + 1));
        lNum2 = _ttol(szBuff.Right(szBuff.GetLength() - (pos + 1)));
    }
    long lMul = lNum1 * lNum2;  // result
    delete[] tcData;
    pfile.Close();  
----------
Good luck

20120131-EE-VQP-002

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