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Problems with my first class.

MrWizard (3)
Hi! Sorry my first post is asking for help.
This is supposed to be able to work with a user's information and, in the end, calculate the student's GPA.

We've(We..the rest of my class) tried troubleshooting and looking up information but it's still not working out and I personally have no idea why.

I'm getting around 52 errors. Help?

Thanks!

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// student.h

#ifndef _student_H
#define _student_H
#include <string.h>


class student
{
 public:
	  // constructors
	  student();               // default constructor
	  student(const student &); // copy constructor

	  // member functions
	  void   SetName(string);
	  string  GetName();
	  
	  void   SetClassi(int);
	  int   GetClassi();
	  
	  void   SetSid(string);
	  string   GetSid();
	  
	  void   SetCtake(int);
	  int   GetCtake();
	  
	  void   SetCcomp(int);
	  int   GetCcomp();
	  
	  void   SetQualpt(int);
	  int   GetQualpt();
	  
	  double CalcGPA();

 private:
	  // data
	  string Name;
	  int Classi;
      string Sid;
      int Ctake;
      int Ccomp;
      int Cualpt;
	  
};

student::student(){
      Name = "Name Here";
	  Classi = 1;
      Sid = "1234567";
      Ctake = 0;
      Ccomp = 0;
      Qualpt = 0;}
      
      // copy constructor
student::student(const student & Object)
{
  Name = Object.Name;
  Sid = Object.Sid;
  Classi = Object.Classi;
  Ctake = Object.Ctake;
  Ccomp = Object.Ccomp;
  Qualpt = Object.Qualpt;
}
// Method to set CredTaken
void student::SetCredTaken(float IncCtaken)
{
     Ctake = IncCtaken;
}

// Method to set Qualpt(quality points)
void student::SetQualPts(float IncQualpt)
{
     QualPt = IncQualpt;
}

// Method to set Ccomp(credits completed)
void student::SetCredComp(float IncCcomp)
{
     Ccomp = IncCcomp;
}

// Method to set Name
void student::SetName(string IncName)
{
     Name = IncName;
}

// Method to set Sid(student ID #)
void student::SetStudNum(string IncSid)
{
     Sid = IncSid;
}

// Method to set Classi(class classification)
void student::SetClassification(string IncClassi)
{
     Classi = IncClassi;
}

// Method to return Ctaken
int student::GetCtaken()
{
  return(Ctaken);
}

// Method to return QualPt
float student::GetQualpt()
{
  return(Qualpt);
} 

// Method to return Ccomp(credits completed)
int student::GetCcomp()
{
  return(Ccomp);
} 

// Method to return Name
string student::GetName()
{
  return(Name);
} 

// Method to return Sid(student ID #)
string student::GetSid()
{
  return(Sid);
} 

// Method to return Classi
int student::GetClassi()
{
  return(Classi);
} 

// Method to find GPA
float CalcGPA::CalcGPA()
{
      return(Qualpt / Ctaken);
}

#endif
MrWizard (3)
Fixed! Haha!

Instead of using "using namespace std" and "#include <string.h>", we changed everything to type oostring and "#include "oostring.cpp".

Apparently, this is a problem with Dev C++?

Still, anyone have any other input?

:D

Also, my code has alot of problems with variable consistency. Forgive that, please, I'm working on it. Misspellings, too.
Last edited on
MrWizard (3)
Fixed:

But why do I have to use "oostring.h" in the test proggie and "oostring.cpp" in the class? If I try to use "oostring.cpp" for both, I get 71 linker errors.

Thanks!


To test class:
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#include <iostream.h>
#include "oostring.h"
#include "studentv2.h"


int main(){
    
    cout << "Hello world";
    
    system("pause");
    return 0;
}


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// student.h

#ifndef _student_H
#define _student_H
#include "oostring.cpp"


class student
{
 public:
	  // constructors
	  student();               // default constructor
	  student(const student &); // copy constructor

	  // member functions
	  void   SetName(oostring);
	  oostring  GetName();
	  
	  void   SetClassi(int);
	  int   GetClassi();
	  
	  void   SetSid(oostring);
	  oostring   GetSid();
	  
	  void   SetCtaken(int);
	  int   GetCtaken();
	  
	  void   SetCcomp(int);
	  int   GetCcomp();
	  
	  void   SetQualpt(int);
	  int   GetQualpt();
	  
	  float CalcGPA();

 private:
	  // data
	  oostring Name;
	  int Classi;
      oostring Sid;
      int Ctaken;
      int Ccomp;
      int Qualpt;
	  
};

student::student(){
      Name = "Name Here";
	  Classi = 1;
      Sid = "1234567";
      Ctaken = 0;
      Ccomp = 0;
      Qualpt = 0;}
      
      // copy constructor
student::student(const student & Object)
{
  Name = Object.Name;
  Sid = Object.Sid;
  Classi = Object.Classi;
  Ctaken = Object.Ctaken;
  Ccomp = Object.Ccomp;
  Qualpt = Object.Qualpt;
}
// Method to set Ctaken
void student::SetCtaken(int IncCtaken)
{
     Ctaken = IncCtaken;
}

// Method to set Qualpt(quality points)
void student::SetQualpt(int IncQualpt)
{
     Qualpt = IncQualpt;
}

// Method to set Ccomp(credits completed)
void student::SetCcomp(int IncCcomp)
{
     Ccomp = IncCcomp;
}

// Method to set Name
void student::SetName(oostring IncName)
{
     Name = IncName;
}

// Method to set Sid(student ID #)
void student::SetSid(oostring IncSid)
{
     Sid = IncSid;
}

// Method to set Classi(class classification)
void student::SetClassi(int IncClassi)
{
     Classi = IncClassi;
}

// Method to return Ctaken
int student::GetCtaken()
{
  return(Ctaken);
}

// Method to return QualPt
int student::GetQualpt()
{
  return(Qualpt);
} 

// Method to return Ccomp(credits completed)
int student::GetCcomp()
{
  return(Ccomp);
} 

// Method to return Name
oostring student::GetName()
{
  return(Name);
} 

// Method to return Sid(student ID #)
oostring student::GetSid()
{
  return(Sid);
} 

// Method to return Classi
int student::GetClassi()
{
  return(Classi);
} 

// Method to find GPA
float student::CalcGPA()
{
      return(Qualpt / Ctaken);
}

#endif
Disch (13742)
no no no, this is wrong. You will have all sorts of linker errors if you #include student.h in more than 1 file.

Here are some general guidelines:

- class bodies go in .h files
- function bodies go in .cpp files
- never include .cpp files

Obligatory link: http://www.cplusplus.com/forum/articles/10627/


The way to structure this would be like this:

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// student.h

#ifndef _student_H
#define _student_H
#include "oostring.h"  // <- .h! don't include .cpp files!


class student
{
 public:
	  // constructors
	  student();               // default constructor
	  student(const student &); // copy constructor
  // ...
};

#endif 

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// student.cpp

#include "student.h"

 // put function bodies in the .cpp file

student::student(){
      Name = "Name Here";
	  Classi = 1;
      Sid = "1234567";
      Ctaken = 0;
      Ccomp = 0;
      Qualpt = 0;}



The reason you get linker errors when you #include cpp files is because this puts the function body in every cpp file. When a function exists in multiple cpp files, the linker sees this as multiple different functions all with the same name, so it doesn't know which one to use.
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