basic i/o question cout<<str;

This is a discussion on basic i/o question cout<<str; within the C++ Programming forums, part of the General Programming Boards category; How can I modify the below text so that it couts all of example.txt? If you want to answer another ...

  1. #1
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    basic i/o question cout<<str;

    How can I modify the below text so that it couts all of example.txt?

    If you want to answer another question:

    1. How can I declare a string, for example
    int a=0;
    char a[256]=test; ((??))



    [code]

    #include <iomanip.h>
    #include <iostream.h>
    #include <fstream.h>
    #include <stdlib.h>
    #include <conio.h>
    #include <time.h>
    #include <ctype.h>


    int main()

    {

    char str[10];

    //Used later

    ofstream a_file("example.txt");

    //Creates an instance of ofstream, and opens example.txt

    a_file<<"This text will now be inside of example.txt";

    //Outputs to example.txt through a_file

    a_file.close();

    //Closes up the file

    ifstream b_file("example.txt");

    //Opens for reading the file

    b_file>>str;

    //Reads one string from the file

    cout<<str;
    cout<<str;
    cout<<str;
    cout<<str;
    cout<<str;
    cout<<str;
    cout<<str;
    cout<<str;

    //Should output 'this'

    b_file.close();

    //Do not forget this!
    getch();

    }

    [c/ode]
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  2. #2
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    Use getline.

    source.getline(placetooutputto,maxnumberofchars,en dingchar);

    so you might use b_file.getline(str,100,'/n');

    But of course you would want to put a /n at the end of the string. or any other character you choose. It will keep going until it finds that character. I'm not sure whether an error will come up or not if you get to the end of a file.

  3. #3
    Registered User rmullen3's Avatar
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    ~

    If you mean displaying all of a file on cout:

    Code:
    #include <iostream>
    #include <fstream>
    
    int main (void) 
    {
    	std::ifstream in ("example.txt");
    	char buf[256];
    
    	while (!in.eof()) 
    	{
    		in.getline(buf,256,'\n');
    		std::cout << buf << std::endl;
    	}
    
    	return (0);
    }
    "He who makes a beast of himself, gets rid of the pain of being a man." Dr. Johnson

  4. #4
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    Now I have the below, which compiles, but crashes when i try to run it.

    Code:
    #include <iomanip.h>
    #include <iostream.h>
    #include <fstream.h>
    #include <stdlib.h>
    #include <conio.h>
    #include <time.h>
    #include <ctype.h>
    
    
    int main()
    
    {
    
      char str[10];  
    
             //Used later
    
      ofstream a_file("example.txt");
    
    			//Creates an instance of ofstream, and opens example.txt
    
      a_file<<"This text will now be inside of example.txt/n";
    
    			//Outputs to example.txt through a_file
    
      a_file.close();
    
    			//Closes up the file
    
       ifstream b_file("example.txt");
    
    			//Opens for reading the file
    
     b_file.getline(str,100,'/n');
    
    
                 //Reads one string from the file
    
    
      cout<<str;
      cout<<str;
      cout<<str;
      cout<<str;
      cout<<str;
      cout<<str;
      cout<<str;
      cout<<str;
    
               //Should output 'this'
    
      b_file.close();
    
               //Do not forget this!
      getch();
    
    }
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  5. #5
    Registered User rmullen3's Avatar
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    ~

    Because you declared str has being a 10 character array, but are trying to read 100 characters into it.

    Also, you're printing the same thing a bunch of times with all those couts, not reading from the file, if that's what you're trying to do...
    "He who makes a beast of himself, gets rid of the pain of being a man." Dr. Johnson

  6. #6
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    Nor does this work.


    Code:
    #include <iostream.h>
    #include <fstream.h>
    #include <stdlib.h>
    #include <conio.h>
    #include <time.h>
    #include <ctype.h>
    
    
    int main()
    
    {
      char str[100];
      ofstream a_file("example.txt");
      a_file<<"This text will now be inside of example.txt/n";
      a_file.close();
       ifstream b_file("example.txt");
     b_file.getline(str,100,'/n');
      b_file.close();
      getch();
    
    }
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  7. #7
    Registered User rmullen3's Avatar
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    The carriage return is "\n" not "/n".

    Also, does not work as in crashes, or does not work as in what you want it to do? The code I posted should work.
    "He who makes a beast of himself, gets rid of the pain of being a man." Dr. Johnson

  8. #8
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    does not work as in freezes up and does not respond
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  9. #9
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    This works fine on my computer :
    Code:
    #include <iostream.h>
    #include <fstream.h>
    #include <stdlib.h>
    #include <conio.h>
    
    
    int main()
    {
    
    	char str[100];
    	ofstream a_file("example.txt");
    	a_file<<"This text will now be inside of example.txt\n";
    	a_file.close();
    	ifstream b_file("example.txt");
    	b_file.getline(str,100,'\n');
    	cout << str << endl;
    	b_file.close();
    	getch();
    	return 0;
    }

  10. #10
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    ah, thanks
    AIM: MarderIII

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