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Class Object Value to String

itsbenbroughton (25)
Hi all, super noobish question here. My instructions say I have to take the values of the objects below and convert them to a string in the method "string toString()", that I can then display via method "display()".

I'm having a really hard time transferring either the values or a string outside of the class to be accessed by main, ultimately.

Sorry for the poorly worded question, I've been coding for 6 weeks now. Thanks in advance for any advice!

I'm sorry if this is too much code. I tried to cut a lot out... The last two methods are where my question is.

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#include <iostream>
#include <string>
#include <cmath>
#include <sstream>
using namespace std;

class iTune
{
private:
   string name;
   string artist;
   int bitrate;
   int total_time;

public:
   // class constants
   static const int MIN_BITRATE;
   static const int MAX_BITRATE;
   static const int DEFAULT_BITRATE;
   static const int MIN_STR_LENGTH;
   static const int MAX_STR_LENGTH;
   static const string DEFAULT_STRING;
   static const int MIN_PLAY_TIME;
   static const int MAX_PLAY_TIME;
   static const int DEFAULT_PLAY_TIME;
   string theString;

   // accessors
   bool setName(string tempName);
   string getName() { return name; }
   bool setArtist(string tempArtist);
   string getArtist() { return artist; }
   bool setBitrate(int tempRate);
   int getBitrate() { return bitrate; }
   bool setTime(int tempTime);
   int getTime() { return total_time; }

   string toString();
   void display();

   // constructors
   iTune();
   iTune(string tempName, string tempArtist, int tempRate, int tempTime);
};

int const iTune::MIN_BITRATE = 64;
int const iTune::MAX_BITRATE = 705;
int const iTune::DEFAULT_BITRATE = 64;
int const iTune::MIN_PLAY_TIME = 1;
int const iTune::MAX_PLAY_TIME = 1000 * 60 * 60;
int const iTune::DEFAULT_PLAY_TIME = 0;
int const iTune::MIN_STR_LENGTH = 1;
int const iTune::MAX_STR_LENGTH = 80;
string const iTune::DEFAULT_STRING = " (undefined) ";

int main()
{
   iTune tune1;

   tune1.setName("Headup");
   tune1.setArtist("Deftones");
   tune1.setBitrate(192);
   tune1.setTime(313000);

   cout << "These are the most played tracks in my collection!\n\n";

   tune1.display();
   
   return 0;
}

iTune::iTune()
{
   setName(DEFAULT_STRING);
   setArtist(DEFAULT_STRING);
   setBitrate(DEFAULT_BITRATE);
   setTime(DEFAULT_PLAY_TIME);
}

iTune::iTune(string tempName, string tempArtist, int tempRate, int tempTime)
{
   if (!setName(tempName))
      setName(DEFAULT_STRING);
   if (!setArtist(tempArtist))
      setArtist(DEFAULT_STRING);
   if (!setBitrate(tempRate))
      setBitrate(DEFAULT_BITRATE);
   if (!setTime(tempTime))
      setTime(DEFAULT_PLAY_TIME);
}

bool iTune::setName(string tempName)
{
   int tempInt;
   tempInt = tempName.length();
   if (tempInt > MAX_STR_LENGTH || tempInt < MIN_STR_LENGTH)
      return false;
   name = tempName;
   return true;
}

bool iTune::setArtist(string tempArtist)
{
   int tempInt;
   tempInt = tempArtist.length();
   if (tempInt > MAX_STR_LENGTH || tempInt < MIN_STR_LENGTH)
      return false;
   artist = tempArtist;
   return true;
}

bool iTune::setBitrate(int tempRate)
{
   if (tempRate > MAX_BITRATE || tempRate < MIN_BITRATE)
      return false;
   bitrate = tempRate;
   return true;
}

bool iTune::setTime(int tempTime)
{
   if (tempTime > MAX_PLAY_TIME || tempTime < MIN_BITRATE)
      return false;
   total_time = tempTime;
   return true;
}

string iTune::toString()
{
   string temp1, temp2;
   stringstream convert;

   convert << bitrate;
   temp1 = convert.str();
   convert << total_time;
   temp2 = convert.str();

   theString = name + " , " + artist + " , " + temp1 + " , " = temp2;

   return theString;
}

void iTune::display()
{
   cout << theString;
}
Last edited on
Peter87 (11238)
You never call toString() anywhere so theString never gets set. I don' think you want theString to be member variable of the class. Why not make theString a local variable in the toString function instead and then you can call toString() in the display function to get the string representation of the object?
MaBunny (66)
Yes,peter said it right. You can put theString variable as a local variable of toString() function.
Try this :
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string iTune::toString()
 { string temp1,theString; 
stringstream convert; 
convert << bitrate<<","<< total_time;
 temp1 = convert.str(); 
 theString = name + " , " + artist + " , " + temp1;
return theString;
}

I didnt include the temp2 variable for my own assumptions,but you can try this to see it it works. 😃
Also,there will be a '+' sign before temp2 in line138.remember tht.
As for this line,
I'm having a really hard time transferring either the values or a string outside of the class to be accessed by main, ultimately

You can do this
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Itune i(string,string,int,int);
string s;
s=i.toString();
//....(other stuff goes here)

I dont kno if the function name is appropriate,but pls reply if you found this helpful.
itsbenbroughton (25)
That's incredibly helpful, Peter87 and MaBunny, and I thank you both! I was able to get it to display something because of the two of you! It's not displaying what I want yet, and I don't know why, but I'm so much closer!

After changing toString() and display() to:

string iTune::toString()
{
   string temp1, temp2, theString;
   stringstream convert;

   convert << bitrate;
   temp1 = convert.str();
   convert << total_time;
   temp2 = convert.str();

   theString = name + " , " + artist + " , " + temp1 + " , " = temp2;

   return theString;
}

void iTune::display()
{
   iTune display;
   string temp;
   temp = display.toString();

   cout << temp << endl;
}


Any idea why my output is:

These are the most played tracks in my collection!

64-858993460
Press any key to continue . . .
AbstractionAnon (6954)
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theString = name + " , " + artist + " , " + temp1 + " , " = temp2;
//                                                        ^ should be +, not =


temp2 (total_time) replaces the entire theString.

You can simplify to_string() considerably:
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string iTune::toString()
{  stringstream ss;

  ss << name << " , " << artist << " , " << bitrate <<" , " << total_time;
  return ss.str(); 
}


Please use CODE tags, not quote tags when posting code.
Last edited on
itsbenbroughton (25)
You all are amazing!Thank you so much! It's displaying now :)

Now I'm having a problem with my set's not setting my private values, so it's displaying my defaults, but I'll start a new thread for that.

Thanks again!
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