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Need help with a problem dealing with files (retriving and checking information)

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Join Date: Jan 2009

Posts: 22

Reputation: jdm is an unknown quantity at this point

Solved Threads: 0

jdm

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Newbie Poster

Need help with a problem dealing with files (retriving and checking information)

Nov 8th, 2009

I'm helping a friend out with some code and I'm having the hardest time figuring out how to do this. I know it is simple, but for the life of me I can't remember how to do it. Any help or advice would be welcomed. Thanks for the help in advance.

Problem: I need to open a file first, then have a user input a 6 digit number then check the file and if it finds it then it will get the name by it and if it doesn't exist in the file then it will say so. I'm having trouble having it run through and check the file. I can have it run through the whole document and output the data and I can check the very first line of data, but after that I can't get it to work at all. It will get the first three data values from the file if it isn't the first number of the file, but it won't get the name or check. I haven't got to the part about output if the number doesn't exit in the file, but I'm not concerned about that part yet. Here is my code. Thanks again for the help.

 Help with Code Tags 
(Toggle Plain Text)
 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
 
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
 
using namespace std; //helps run the program
int main()
{
       double sticker;
       string Fname;
       double first;
       string second;
       second = "not";
 
       ifstream dataIn;  //for the data input
       dataIn.open("HWK5.txt");
 
       cout << "sticker:  ";
       cin >> sticker;
 
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;;
                    if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
                     else if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
 
       }
 
 
        cout << "here: " << Fname << endl;
       dataIn.close();
      system("Pause");
      return 0;
       }
 
 
/*
       
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;
                  
                      if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
  else if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
       }
       */
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
 
using namespace std; //helps run the program
int main()
{
       double sticker;
       string Fname;
       double first;
       string second;
       second = "not";

       ifstream dataIn;  //for the data input
       dataIn.open("HWK5.txt");

       cout << "sticker:  ";
       cin >> sticker;
       
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;;
                    if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
                     else if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
 
       }


        cout << "here: " << Fname << endl;
       dataIn.close();
      system("Pause");
      return 0;
       }


/*
       
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;
                  
                      if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
  else if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
       }
       */
     Help with Code Tags   C++ Syntax (Toggle Plain Text)     #include <iostream>#include <iomanip>#include <fstream>#include <string> using namespace std; //helps run the programint main(){       double sticker;       string Fname;       double first;       string second;       second = "not";        ifstream dataIn;  //for the data input       dataIn.open("HWK5.txt");        cout << "sticker:  ";       cin >> sticker;        while(dataIn)       {                    dataIn >> first;                    cout << first << endl;;                    if (first == sticker)                    {                     dataIn >> second;                     cout << second << endl;                     Fname = second;                     }                     else if (first != sticker){                        dataIn >> first;                        cout << first << endl; }        }          cout << "here: " << Fname << endl;       dataIn.close();      system("Pause");      return 0;       }  /*              while(dataIn)       {                    dataIn >> first;                    cout << first << endl;                                        if (first != sticker){                        dataIn >> first;                        cout << first << endl; }  else if (first == sticker)                    {                     dataIn >> second;                     cout << second << endl;                     Fname = second;                     }       }       */ 
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
 
using namespace std; //helps run the program
int main()
{
       double sticker;
       string Fname;
       double first;
       string second;
       second = "not";

       ifstream dataIn;  //for the data input
       dataIn.open("HWK5.txt");

       cout << "sticker:  ";
       cin >> sticker;
       
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;;
                    if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
                     else if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
 
       }


        cout << "here: " << Fname << endl;
       dataIn.close();
      system("Pause");
      return 0;
       }


/*
       
       while(dataIn)
       {
                    dataIn >> first;
                    cout << first << endl;
                  
                      if (first != sticker){
                        dataIn >> first;
                        cout << first << endl; }
  else if (first == sticker)
                    {
                     dataIn >> second;
                     cout << second << endl;
                     Fname = second;
                     }
       }
       */  

Sincerely yours;

jdm

•

Join Date: Aug 2009

Posts: 6

Reputation: ebrutekim is an unknown quantity at this point

Solved Threads: 1

ebrutekim

Offline

Newbie Poster

Nov 11th, 2009

For checking every line of the data, assuming each number has its own line, try this:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
string sticker;
string line;
 
dataIn.open("HWK5.txt");
 
if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));
 
        if(stickCheck == sticker)
        {
            //once numbers match perform your function
        }
    }
    dataIn.close();
}
string sticker;
string line;

dataIn.open("HWK5.txt");

if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));

        if(stickCheck == sticker)
        {
            //once numbers match perform your function
        }
    }
    dataIn.close();
}

Maybe I misread your question, but I gathered that you couldn't get your inputted number to check against all the values in your file.

For checking whether the number is found, you might include something like:

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
string sticker;
string line;
 
bool numFound = false;
 
dataIn.open("HWK5.txt");
 
if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));
 
        if(stickCheck == sticker)
        {
            //once numbers match perform your function
            numFound = true;
        }
    }
    if(numFound == false)
    {
        cout << "Number not found!" << endl;
    }
    dataIn.close();
}
else
{
    cout << "Unable to open file!";
}
string sticker;
string line;

bool numFound = false;

dataIn.open("HWK5.txt");

if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));

        if(stickCheck == sticker)
        {
            //once numbers match perform your function
            numFound = true;
        }
    }
    if(numFound == false)
    {
        cout << "Number not found!" << endl;
    }
    dataIn.close();
}
else
{
    cout << "Unable to open file!";
}

Hope this helps.

"Don't be afraid to give your best to what seemingly are small jobs. Every time you conquer one it makes you that much stronger. If you do the little jobs well, the big ones will tend to take care of themselves." - Dale Carnegie

\m/

•

Join Date: Jan 2009

Posts: 22

Reputation: jdm is an unknown quantity at this point

Solved Threads: 0

jdm

Offline

Newbie Poster

Nov 11th, 2009

Thank you for your help. I will give that a try and let you know how it work.

Sincerely yours;

jdm

11

•

Originally Posted by ebrutekim

For checking every line of the data, assuming each number has its own line, try this:
Help with Code Tags

C++ Syntax (Toggle Plain Text)
string sticker;
string line;
 
dataIn.open("HWK5.txt");
 
if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));
 
        if(stickCheck == sticker)
        {
            //once numbers match perform your function
        }
    }
    dataIn.close();
}
string sticker; string line; dataIn.open("HWK5.txt"); if (dataIn.is_open()) { while (! dataIn.eof() ) { getline (dataIn,line); stickCheck = (atoi(line.c_str())); if(stickCheck == sticker) { //once numbers match perform your function } } dataIn.close(); }
Maybe I misread your question, but I gathered that you couldn't get your inputted number to check against all the values in your file.

For checking whether the number is found, you might include something like:
Help with Code Tags

C++ Syntax (Toggle Plain Text)
string sticker;
string line;
 
bool numFound = false;
 
dataIn.open("HWK5.txt");
 
if (dataIn.is_open())
{
    while (! dataIn.eof() )
    {
        getline (dataIn,line);
        stickCheck = (atoi(line.c_str()));
 
        if(stickCheck == sticker)
        {
            //once numbers match perform your function
            numFound = true;
        }
    }
    if(numFound == false)
    {
        cout << "Number not found!" << endl;
    }
    dataIn.close();
}
else
{
    cout << "Unable to open file!";
}
string sticker; string line; bool numFound = false; dataIn.open("HWK5.txt"); if (dataIn.is_open()) { while (! dataIn.eof() ) { getline (dataIn,line); stickCheck = (atoi(line.c_str())); if(stickCheck == sticker) { //once numbers match perform your function numFound = true; } } if(numFound == false) { cout << "Number not found!" << endl; } dataIn.close(); } else { cout << "Unable to open file!"; }
Hope this helps.

•

Join Date: Jan 2009

Posts: 22

Reputation: jdm is an unknown quantity at this point

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jdm

Offline

Newbie Poster

Getting code to work

30 Days Ago

I couldn't get it to work. Also the file looks something like this:

111111 Hill
222222 Sam

The numbers are on the same line as the name. Thanks for the help.

Sincerely yours;

jdm

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Join Date: Sep 2009

Posts: 618

Reputation: jonsca is on a distinguished road

Solved Threads: 82

jonsca

Offline

Practically a Master Poster

30 Days Ago

The atoi() function should strip out the text as long as the numbers are first. Either that or you could change his getline to one with a delimiter of ' ' (space) http://www.cplusplus.com/reference/i...tream/getline/