Reading file

[newguy194]

I have written the skeleton for a program which is supposed to dissect a text file by first getting the entire contents of the textfile as a string, then searching that string for a matching first word, then skipping over a delimiter and returning the correct word. For some reason it does not return anything, and I do not see where my error is occuring.

#include <cstdlib>
#include <iostream>
#include <fstream>
#include <conio.h>
using namespace std;
 
int main(int argc, char *argv[])
{
    string input = "";
    string output = "";
    string search = "";
    string component = "";
    int x = 0;
    cout<<"input:";
    getline(cin, input);
    fstream file("read.txt");
    while(!file.eof())
    {
    getline(file, search);
    }        
         file.close();
         
    while(component != input)
    {
       if(search[x] == '|')
       {
         component.erase(component.size());
         while(search[x] != '\r')
         {
           x++;
           }
       }
       else{component += search[x]; x++;}
    }
         x++;
         while(search[x] != '\r')
         {
           output += search[x];
           }
           
         cout<<output;
         getch();
    return EXIT_SUCCESS;
}

[jwwicks]

Hello,

I have written the skeleton for a program which is supposed to dissect a text file by first getting the entire contents of the textfile as a string, then searching that string for a matching first word, then skipping over a delimiter and returning the correct word. For some reason it does not return anything, and I do not see where my error is occuring.

    while(!file.eof())
    {
    getline(file, search);
    }        
         file.close();
         
}

Your problem is here with the first while. Unless the "input" is on the last line of the text file I dont believe you'll get a match. Try putting all the lines into a vector of strings. getline doesn't append the next line it overwrites search with the new line.

John

[newguy194]

Hello,



Your problem is here with the first while. Unless the "input" is on the last line of the text file I dont believe you'll get a match. Try putting all the lines into a vector of strings. getline doesn't append the next line it overwrites search with the new line.

John

Thanks for noticing that problem john, but I am currently testing it with a file where that is exactly the case, so I do not believe that is my main error. Although I was wondering whether simply using

  while(!file.eof())
    {
    getline(file, search);
    contents+=search;
    }

would remedy the problem you noticed.

[newguy194]

I have solved the problems I was encountering by reformatting the file I am using and implementing vectors here:

#include <cstdlib>
#include <iostream>
#include <fstream>
#include <conio.h>
#include <vector>
using namespace std;
 
int main(int argc, char *argv[])
{
    vector<string> contents;
    string input;
    string output;
    string search;
    int x = 0;
    string component = "";
    cout<<"input:";
    getline(cin, input);
    fstream file("read.txt");
    while(!file.eof())
    {
    getline(file, search);
    contents.push_back(search);
    }
    file.close();
    for(int y = 0;y<contents.size()-1;y+=2)
    {
            if(contents.at(y) == input)
            {
              component = contents.at(y+1);
              }
    }
    cout<<component;
    getch();
    return EXIT_SUCCESS;
}