Reading from text file into array

[stanwaka]

Hi i'm pretty new to C++ (well very new!) and i need to read the information from a text file into an array. The kind of data i'll be using is a simple list of names. This is my first attempt at;

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

int main () 
{
  string array[5];                          // creates array to hold names
  short loop;                               //short for loop for input
  short loop2;                               //short for loop for output
  string line;                              //this will contain the data read from the file
  ifstream myfile ("example.txt");          //opening the file.
  if (myfile.is_open())                     //if the file is open
  {
    while (! myfile.eof() )                 //while the end of file is NOT reached
    {
      getline (myfile,line);                //get one line from the file
      cout << line <<  endl;                //and output it
        for (loop=0; loop<5;loop++)         //criteria for input loop (as array 0-5)
      {
      array[loop]=line;                     //output loop statement
      };
        for (loop2=0; loop2<5;loop2++)      //criteria for output loop (as array 0-5)
      {
      cout << array[loop2];                     //loop statement
      };
    }
    myfile.close();                         //closing the file
  }
  else cout << "Unable to open file";       //if the file is not open output 
  system("PAUSE");
    

       system("PAUSE");
  return 0; 
}

The data appears in a file that looks like this:
john
dave
paul
jack
adam

Thanks for your time.

[GreenDay2001]

Use [ code ] [/ code ] (without spaces) tags to post your code.

Is this what you want....
You can simultaneously read line and put it into array[] and line, so you dont need two loops.

#include <iostream>
#include <fstream>
#include <string>
using namespace std;

int main ()
{
    string array[5]; // creates array to hold names

    short loop=0; //short for loop for input

    string line; //this will contain the data read from the file
    ifstream myfile ("example.txt"); //opening the file.
    if (myfile.is_open()) //if the file is open
    {
        while (! myfile.eof() ) //while the end of file is NOT reached
        {
            getline (myfile,line); //get one line from the file
            array[loop] = line;
            cout << array[loop] << endl; //and output it
            loop++;
        }
        myfile.close(); //closing the file
    }
    else cout << "Unable to open file"; //if the file is not open output

    system("PAUSE");
    return 0;
}

[stanwaka]

Thats it! Thanks alot Vishesh!

[WaltP]

Problem #1:

while (! myfile.eof() )     //while the end of file is NOT reached

See this ( .eof() is identical to feof() Problem #2:

system("PAUSE");

See this

[~s.o.s~]

Vishesh, like Walter said, don't use EOF or you just end up writing an additonal condition to prevent the fetching of the last record, one too many times.

Instead use, while ( getline (file_stream, my_string ).good () ) And as for system ( "PAUSE" ) read the article posted.

[hannad]

#include <iostream> //For Input/Output
#include <fstream> //For File Input/Output
#include <string> //For Saving The Line Into The Array
using namespace std;
int main ()
{
	string array[5]; //Array to save the line on
	int loop=0; //Index of array
	int loop2;
	string line; //The line taken from the *.txt source
	ifstream myfile ("example.txt"); //To read from the *.txt File
	if (myfile.is_open()) //Checking if the file can be opened
	{
		while (! myfile.eof() ) //Runs while the file is NOT at the end
		{
			getline (myfile,line); //Gets a single line from example.txt
			array[loop]=line; //Saves that line in the array
			loop++; //Does an increment to the variable 'loop'
		}
		myfile.close(); //Closes the file
	}
	else cout << "Unable to open file"<<endl; //Gives that sentence if the file can't be opened
	for(loop2=0;loop2<=loop;loop2++) //For loop make to cout the lines stored
		cout<<array[loop2]<<endl;    //inside of the variable 'array'
	return 0;
}

Your code made the 5 lines as output on the command prompt, but only the first line was saved in the variable array.

My code as I edited yours, saves the 5 lines from the file into the array and then it outputs them. Hope you benefit from this.

=EDIT= I'm sorry, I didn't see that you posted a corrected code before me. I didn't continue the rest of the thread. So sorry :)

[ilileve]

hiii guys im really new about c++ i got a lot of problem...
and i've an home work how to open a text in array ???
and the out should be like this :

you
he
she
him
her
continue until 50 lines....

help please ?????????