How to read whole line including white space?

[JWest46088]

I am making a program that asks the user to enter some information and then enters it into a text file, but I can't figure out how to read a whole line with spaces in it. When the user enters a line with spaces in it, only the first word appears in the text file. Can anyone help me figure this out? Thanks in advance.

Here is my program:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
    
int main ()
{
  string line;
  ofstream myfile("playlist.txt");
  if(myfile.is_open())
  {
    cout << "Enter artist: ";
    cin >> line;
    myfile << line << endl;
    cout << "Enter album: ";
    cin >> line;
    myfile << line << endl;
    cout << "Enter track: ";
    cin >> line;
    myfile << line << endl;
    cout << "Enter song: ";
    cin >> line;
    myfile << line << endl;
    cout << "Enter genre: ";
    cin >> line;
    myfile << line << endl;
    myfile.close();
  }
  else
    cout << "Unable to open file.";

  return 0;
}

When I enter 2pac for artist and Greatest Hits for album, it skips the part where the user is supposed to enter the track and goes to the song so I enter the song I Get Around, and it skips the genre part.

Here is what it does:

Enter artist: 2pac
Enter album: Greatest Hits
Enter track: Enter song: I Get Around
Enter genre:

Here is the text file it outputs it to:

2pac
Greatest
Hits
I
Get

Can somebody please help me?

[ilikepython]

I am making a program that asks the user to enter some information and then enters it into a text file, but I can't figure out how to read a whole line with spaces in it. When the user enters a line with spaces in it, only the first word appears in the text file. Can anyone help me figure this out? Thanks in advance.

Here is my program:

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

int main ()
{
string line;
ofstream myfile("playlis t.txt");
if(myfile.is_op en())
{
cout << "Enter artist: ";
cin >> line;
myfile << line << endl;
cout << "Enter album: ";
cin >> line;
myfile << line << endl;
cout << "Enter track: ";
cin >> line;
myfile << line << endl;
cout << "Enter song: ";
cin >> line;
myfile << line << endl;
cout << "Enter genre: ";
cin >> line;
myfile << line << endl;
myfile.close();
}
else
cout << "Unable to open file.";

return 0;
}



When I enter 2pac for artist and Greatest Hits for album, it skips the part where the user is supposed to enter the track and goes to the song so I enter the song I Get Around, and it skips the genre part.

Here is what it does:

Enter artist: 2pac
Enter album: Greatest Hits
Enter track: Enter song: I Get Around
Enter genre:

Here is the text file it outputs it to:

2pac
Greatest
Hits
I
Get

Can somebody please help me?

You should use the getline() function. That takes a whole line from an input stream:

cin.getline(buffer, size_of_line);

[Ganon11]

I've also used the getline function like this:

getline(cin, myStringVar);

Keep in mind that, after you call getline, there is still a newline character \n in the stream. You should use a cin.get() call or a cin.ignore() call to get rid of this.

[JWest46088]

You should use the getline() function. That takes a whole line from an input stream:

cin.getline(buffer, size_of_line);

What is buffer? What would I put in for it?

cin.getline(buf fer, 10);

Would that be right?

[Ganon11]

In this case, buffer is a character array, which is the convention for getting strings without using the string class. I'm not sure if cin.getline() will work with a string argument.

[JWest46088]

In this case, buffer is a character array, which is the convention for getting strings without using the string class. I'm not sure if cin.getline() will work with a string argument.

I got it! Thanks! Don't leave though. I'll probably need more help. ;P Thanks again.

[JWest46088]

I got it! Thanks! Don't leave though. I'll probably need more help. ;P Thanks again.

I want the user to enter information, such as names, and then I want to ask them after they entered the first name if they want to enter another name. How would I do that?

This is what I have so far:

 cout << "Would you like to enter an artist's information?  ";
    cin >> answer;

    if(answer = 'Y' || 'y')
    {
      cout << "Enter artist: ";
      cin.getline(line, 50);// >> line;
      myfile << line << endl;
      cout << "Enter album: ";
      cin.getline(line, 50);// >> line;
      myfile << line << endl;
      cout << "Enter track: ";
      cin.getline(line, 50);// >> line;
      myfile << line << endl;
      cout << "Enter song: ";
      cin.getline(line, 50);// >> line;
                     .
                     .
                     .
}

Here's what happens:

Would you like to enter an artist's information? y
Enter artist: Enter album: 2pac
Enter track: 2
Enter song: f
Enter genre: a

It skips where you enter the artist name. Also, it doesn't matter whether you put y or a;osidhfasd in after it asks to enter more info. It goes on no matter what.

[ilikepython]

I want the user to enter information, such as names, and then I want to ask them after they entered the first name if they want to enter another name. How would I do that?

This is what I have so far:

cout << "Would you like to enter an artist's information? ";
cin >> answer;

if(answer = 'Y' || 'y')
{
cout << "Enter artist: ";
cin.getline(lin e, 50);// >> line;
myfile << line << endl;
cout << "Enter album: ";
cin.getline(lin e, 50);// >> line;
myfile << line << endl;
cout << "Enter track: ";
cin.getline(lin e, 50);// >> line;
myfile << line << endl;
cout << "Enter song: ";
cin.getline(lin e, 50);// >> line;
.
.
.
}

Here's what happens:

Would you like to enter an artist's information? y
Enter artist: Enter album: 2pac
Enter track: 2
Enter song: f
Enter genre: a

It skips where you enter the artist name. Also, it doesn't matter whether you put y or a;osidhfasd in after it asks to enter more info. It goes on no matter what.

Try adding cin.ignore() after you ask for the input. Also, you have "if (answer = 'y'|'Y')"
You want "if (answer == 'Y'|'y')".
If you want to ask for more than one artist than you can use a while loop that runs if the user said 'y' or 'Y'.

[Ganon11]

Even this if condition will not work. I can see what you're trying to say - execute if the user enters 'y' or 'Y' - but that's not how the compiler will read it. You should instead type if (answer == 'Y' || answer == 'y').

[ilikepython]

Even this if condition will not work. I can see what you're trying to say - execute if the user enters 'y' or 'Y' - but that's not how the compiler will read it. You should instead type if (answer == 'Y' || answer == 'y').

Oh yes, that's what I meant, stupid mistake. I just wanted to point out the double equal sign.

[Ganon11]

No problem - it just goes to show you that we all make mistakes :D

[JWest46088]

I revised my program. It does the same thing. The input( ) function is supposed to be called, which gets the input from the user. Then, the moreInput( ) function is supposed to be called to ask the user if they want to enter more information, and if they type Y or y, it calls the input( ) function again, but I am getting errors that I have no clue what they mean.

Here is my program:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
 
int main ()
{   
  input();
  moreInput();
   
  return 0;
}
    
void input()
{
  char line[100];
    
  ofstream myfile("playlist.txt");
  if(myfile.is_open())
  {
    cout << "Enter artist: ";
    cin.getline(line, 50); 
    myfile << line << endl; 
    cout << "Enter album: ";
    cin.getline(line, 50); 
    myfile << line << endl;
    cout << "Enter track: ";
    cin.getline(line, 50);
    myfile << line << endl;
    cout << "Enter song: ";
    cin.getline(line, 50);   
    myfile << line << endl;
    cout << "Enter genre: ";
    cin.getline(line, 50);  
    myfile << line << endl;
    myfile.close();
  }
  else
    cout << "Unable to open file.";
}
    
void moreInput()
{
  char answer;
  cout << "Would you like to enter more information into your library? (Y/N)  ";
  cin >> answer;
   
  if(answer == 'Y' || answer == 'y')
    cin.ignore();
    input();
}

Here are the errors:

playlist_v2.cpp : In function `int main()':
playlist_v2.cpp :8: error: `input' undeclared (first use this function)
playlist_v2.cpp :8: error: (Each undeclared identifier is reported only once for each function it appears in.)
playlist_v2.cpp :9: error: `moreInput' undeclared (first use this function)
playlist_v2.cpp : In function `void input()':
playlist_v2.cpp :15: error: `void input()' used prior to declaration
playlist_v2.cpp : In function `void moreInput()':
playlist_v2.cpp :43: error: `void moreInput()' used prior to declaration


Can someone tell me what these errors mean?

[ilikepython]

I revised my program. It does the same thing. The input( ) function is supposed to be called, which gets the input from the user. Then, the moreInput( ) function is supposed to be called to ask the user if they want to enter more information, and if they type Y or y, it calls the input( ) function again, but I am getting errors that I have no clue what they mean.

Here is my program:

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
 
int main ()
{   
  input();
  moreInput();
   
  return 0;
}
    
void input()
{
  char line[100];
    
  ofstream myfile("playlist.txt");
  if(myfile.is_open())
  {
    cout << "Enter artist: ";
    cin.getline(line, 50); 
    myfile << line << endl; 
    cout << "Enter album: ";
    cin.getline(line, 50); 
    myfile << line << endl;
    cout << "Enter track: ";
    cin.getline(line, 50);
    myfile << line << endl;
    cout << "Enter song: ";
    cin.getline(line, 50);   
    myfile << line << endl;
    cout << "Enter genre: ";
    cin.getline(line, 50);  
    myfile << line << endl;
    myfile.close();
  }
  else
    cout << "Unable to open file.";
}
    
void moreInput()
{
  char answer;
  cout << "Would you like to enter more information into your library? (Y/N)  ";
  cin >> answer;
   
  if(answer == 'Y' || answer == 'y')
    cin.ignore();
    input();
}

Here are the errors:

playlist_v2.cpp : In function `int main()':
playlist_v2.cpp :8: error: `input' undeclared (first use this function)
playlist_v2.cpp :8: error: (Each undeclared identifier is reported only once for each function it appears in.)
playlist_v2.cpp :9: error: `moreInput' undeclared (first use this function)
playlist_v2.cpp : In function `void input()':
playlist_v2.cpp :15: error: `void input()' used prior to declaration
playlist_v2.cpp : In function `void moreInput()':
playlist_v2.cpp :43: error: `void moreInput()' used prior to declaration


Can someone tell me what these errors mean?

Try putting prototypes at the top of your file. You need those because when main runs it hasn't yet seen those functions:

void input();  // notice the semicolons
void moreInput();
//rest of program

Also, your last if statement in moreInput() should have braces otherwise it will call input no matter what the user enters.

[JWest46088]

Yes, I just realized that. Doh...

New problem. I ask the user if they want to enter more information and they enter y or Y. Then, after they entered new information, it overwrites the existing information in the text file. How would I make it so it wouldn't do this?

[JWest46088]

Yes, I just realized that. Doh...

New problem. I ask the user if they want to enter more information and they enter y or Y. Then, after they entered new information, it overwrites the existing information in the text file. How would I make it so it wouldn't do this?

I probably should use append, huh?