Hi, I'm having an issue in my program when I try to call delete in my destructor.
Can someone take a look and see what I doing wrong? I've looked it over and over but I just can't figure out what's wrong.
destructor code:
StudentRecord::~StudentRecord(){ // Destructor
delete[] m_firstName;
delete[] m_lastName;
}and this is my constructor code:
StudentRecord::StudentRecord(char* first,char* last,unsigned int id,float mark){ // Overloaded constructor
m_firstName = strcpy(new char[strlen(first)+1],first);
m_lastName = strcpy(new char[strlen(last)+1],last);
m_id = id;
m_mark = mark;
}Here is the full code for my project in case it's needed.
StudentRecord.h
#ifndef STUDENTRECORD_H
#define STUDENTRECORD_H
class StudentRecord{
char* m_firstName;
char* m_lastName;
unsigned int m_id;
float m_mark;
public:
StudentRecord();
StudentRecord(char*,char*,unsigned int,float);
StudentRecord(StudentRecord&);
~StudentRecord();
StudentRecord& operator=(StudentRecord&);
bool operator>(StudentRecord&);
bool operator<(StudentRecord&);
void Report();
char* GetFirstName(){return m_firstName;}
char* GetLastName(){return m_lastName;}
unsigned int GetID(){return m_id;}
float GetMark(){return m_mark;}
};
#endifStudentRecord.cpp
#include <iostream>
#include "StudentRecord.h"
using namespace std;
StudentRecord::StudentRecord(){ // Default constructor
m_firstName = NULL;
m_lastName = NULL;
m_id = 0;
m_mark = 0.00;
}
StudentRecord::StudentRecord(char* first,char* last,unsigned int id,float mark){ // Overloaded constructor
m_firstName = strcpy(new char[strlen(first)+1],first);
m_lastName = strcpy(new char[strlen(last)+1],last);
m_id = id;
m_mark = mark;
}
StudentRecord::StudentRecord(StudentRecord& ref){ // Copy constructor
*this = ref;
}
StudentRecord::~StudentRecord(){ // Destructor
delete[] m_firstName;
delete[] m_lastName;
}
StudentRecord& StudentRecord::operator=(StudentRecord& ref){ // Overloaded = operator
m_firstName = ref.m_firstName;
m_lastName = ref.m_lastName;
m_id = ref.m_id;
m_mark = ref.m_mark;
return *this;
}
bool StudentRecord::operator>(StudentRecord& ref){ // Overloaded > operator
if(m_mark > ref.m_mark)
return true;
else
return false;
}
bool StudentRecord::operator<(StudentRecord& ref){ // Overloaded < operator
if(m_mark < ref.m_mark)
return true;
else
return false;
}
void StudentRecord::Report(){ // Print class members
cout<<m_firstName<<" "<<m_lastName<<" "<<m_id<<" "<<m_mark<<endl;
}StudentDatabase.h
#include "StudentRecord.h"
#ifndef STUDENTDATABASE_H
#define STUDENTDATABASE_H
class StudentDatabase{
char* m_DatabaseName;
StudentRecord** m_ppRecords;
unsigned int m_numRecords;
char* m_FileName;
public:
StudentDatabase();
~StudentDatabase();
bool OpenFile(void);
void Report(void);
void AddRecord(void);
void DeleteRecord(void);
void HighestMark(void);
void LowestMark(void);
};
#endifStudentDatabase.cpp
#include <iostream>
#include <fstream>
#include "StudentDatabase.h"
using namespace std;
StudentDatabase::StudentDatabase(){
m_ppRecords = new (StudentRecord*);
m_numRecords = 0;
}
StudentDatabase::~StudentDatabase(){
delete[] m_ppRecords;
}
bool StudentDatabase::OpenFile(void){
char fName[50],lName[50],FileName[140]; // Temporary variables for first and last name
unsigned int id; // Temporary variable for id
float grade; // Temporary varialbe for mark
ofstream out; // File output stream
ifstream in; // File input stream
if(m_ppRecords == NULL) // Make sure the array memory is allocated
return false;
cout<<"OPEN FILE\n";
cout<<"Please enter the name of the file to open: ";
cin>>FileName;
m_FileName = new char(sizeof(FileName));
strcpy(m_FileName,FileName);
in.open(m_FileName,fstream::in); // Get the file name then open try to open the file
if(in.is_open()){ // Check if the file is opened
while(in>>fName>>lName>>id>>grade){ // Get input from the file then assign it to the record
m_ppRecords[m_numRecords] = (new StudentRecord(fName,lName,id,grade));
m_numRecords++;
}
cout<<"READIN RECORDS INTO MEMORY\n";
cout<<"There are "<<m_numRecords<<" student records.\n";
}
else{ // Create the file if it's not opened
in.close();
in.clear();
out.open(m_FileName);
out.close();
in.open(m_FileName);
if(in.is_open()){
cout<<"Opening file for 1st time\n";
cout<<"READIN RECORDS INTO MEMORY\n";
cout<<"There are "<<m_numRecords<<" student records.\n";
}
else
return false; // Error creating the file
}
in.close();
return true;
}
void StudentDatabase::Report(void){
for(unsigned int i=0;i<m_numRecords;i++){
cout<<"Record #"<<i<<endl;
m_ppRecords[i]->Report();
}
}
void StudentDatabase::AddRecord(void){
char fName[50],lName[50]; // Temp variables for first and last name
unsigned int id; // Temp variable for id
float grade; // Temp variable for mark
int getInput = 1; // Used to end the while loop for input
bool bFailed = true; // Used to stop input on error
while(getInput){ // Start getting input
cout<<"Please enter first name:\n";
cin>>fName; // Get first name input
if(!cin.good()){ // Check if there's an error during input
cout<<"Error getting input\n"; //Used each time the user is asked for input
bFailed = cin.fail();
cin.clear();
cin.ignore(128,'\n');
break;
}
cout<<"Please enter last name:\n";
cin>>lName; // Get last name input
if(!cin.good()){
cout<<"Error getting input\n";
bFailed = cin.fail();
cin.clear();
cin.ignore(128,'\n');
break;
}
cout<<"Please enter ID:\n";
cin>>id; // Get id input
if(!cin.good()){
cout<<"BAD ID INPUT\n";
bFailed = cin.fail();
cin.clear();
cin.ignore(128,'\n');
break;
}
cout<<"Please enter mark:\n";
cin>>grade; // Get mark input
if(!cin.good()){
cout<<"BAD MARK INPUT\n";
bFailed = cin.fail();
cin.clear();
cin.ignore(128,'\n');
break;
}
getInput = 0;
}
if(bFailed==true){ // If input didn't fail assign the values to the record
m_ppRecords[m_numRecords] = (new StudentRecord(fName,lName,id,grade));
m_numRecords++;
cout<<"Number of Records = "<<m_numRecords<<endl;
cout<<"ADDED A NEW RECORD IN MEMORY OK"<<endl;
}
}
void StudentDatabase::DeleteRecord(void){
delete m_ppRecords[m_numRecords];
m_numRecords--;
}
void StudentDatabase::HighestMark(void){
int id_Highest = 0;
for(int i=0;i<m_numRecords;i++){
if(m_ppRecords[id_Highest]<m_ppRecords[i])
id_Highest = m_ppRecords[i]->GetID();
}
m_ppRecords[id_Highest]->Report();
}
void StudentDatabase::LowestMark(void){
int id_Lowest = 0;
for(int i=0;i<m_numRecords;i++){
if(m_ppRecords[id_Lowest]<m_ppRecords[i])
id_Lowest = m_ppRecords[i]->GetID();
}
m_ppRecords[id_Lowest]->Report();
}