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POCreate array of class objects inside another class
 

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  1. POCreate array of class objects inside another class
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    <p>I have a problem. I'm trying to create an array of different class objects derived from a base class. This is the code:</p> <pre><code> class Cdvd{ protected: char *numeArtist; //numer artist sau film char *tip;// CD sau DVD int cantitate; //numar de CD/DVD din baza de date int pret; //pret per unitate int cod_intern; //cod intern produs. Spre exemplu 0 pentru un film horror. void scriereInFisier(std::fstream &amp;out); //scriere in fisierul cu produse public: Cdvd(); //constructor produs implicit Cdvd(const Cdvd &amp;cdvd); //constructor produs cu parametru alt produs Cdvd(char *artist, char *tip, int cant, int pret, int cod_int); //constructor produs cu parametri ~Cdvd(); //destructor produs char *getNume(); //returneaza pointer la numele artistului sau filmului void parseFis(char *artist, char *tip, int cant, int pret, int cod_int); virtual void afisCamp()=0; //afiseaza campurile produsului }; class CD : public Cdvd{ private: char *genMuzica; //genul muzicii char *extensie; //extensia fisierelor audio int nrTrackuri; //numar melodii int lungime; //lungime totala melodii public: CD(); //constructor implicit cd CD(char *artist, int cant, int pret, int cod_int, char *genMuzica, char *extensie, int nrTrackuri, int lungime); CD(const CD &amp;cd); //constructor cd cu parametru alt cd ~CD(); //destructor cd void parseFis(char *artist, int cant, int pret, int cod_int, char *genMuzica, char *extensie, int nrTrackuri, int lungime); void afisCamp(); //afiseaza campurile cd-ului }; class DVD : public Cdvd{ private: char *genFilm; char *extensie; int lungime; public: DVD(); DVD(char *artist, int cant, int pret, int cod_int, char *genFilm, char *extensie, int lungime); ~DVD(){cout&lt;&lt;"~DVD()"&lt;&lt;endl;}; void parseFis(char *artist, int cant, int pret, int cod_int, char *genFilm, char *extensie, int lungime); void afisCamp(); }; </code></pre> <p>Now, I'm trying to create from this class an array of CD and DVD:</p> <pre><code>class ListaProduse{ static const int dimMax=20; //dimensiune maxima lista produse Cdvd **vector; //vector in care se retin produsele int nrProduse; //retine cate produse sunt in baza de date public: ListaProduse(); ~ListaProduse(); void adauga(std::fstream &amp;in); void afisare(); }; </code></pre> <p>and this is the code for ListaProduse class:</p> <pre><code>ListaProduse::ListaProduse() { nrProduse=0; vector=new Cdvd*[dimMax]; } ListaProduse::~ListaProduse() { if(nrProduse&gt;0) { delete vector; } } void ListaProduse::adauga(std::fstream &amp;in) { if(in.is_open()) { int pret,cant,cod; char temp1[20],aux1[20]; char aux; while(!in.eof()) { in&gt;&gt;aux; in&gt;&gt;temp1; char *teemp1=new char[strlen(temp1)+1]; strcpy(teemp1,temp1); in&gt;&gt;pret; in&gt;&gt;cant; in&gt;&gt;cod; switch(aux){ case 'C':{ int nrTr,lung; in&gt;&gt;aux1; char *auxiliar1=new char[strlen(aux1)+1]; strcpy(auxiliar1,aux1); in&gt;&gt;aux1; char *auxiliar2=new char[strlen(aux1)+1]; strcpy(auxiliar2,aux1); in&gt;&gt;nrTr; in&gt;&gt;lung; CD *x; x=new CD; x-&gt;parseFis(teemp1,pret,cant,cod,auxiliar1,auxiliar2,nrTr,lung); vector[nrProduse]=x; vector[nrProduse]-&gt;afisCamp(); //cout&lt;&lt;vector[nrProduse]-&gt;numeArtist; nrProduse++; break; } case 'D':{ int lung; in&gt;&gt;aux1; char *auxiliar1=new char[strlen(aux1)+1]; strcpy(auxiliar1,aux1); in&gt;&gt;aux1; char *auxiliar2=new char[strlen(aux1)+1]; strcpy(auxiliar2,aux1); in&gt;&gt;lung; DVD *x; x=new DVD; x-&gt;parseFis(teemp1,pret,cant,cod,auxiliar1,auxiliar2,lung); vector[nrProduse]=x; vector[nrProduse]-&gt;afisCamp(); nrProduse++; break; } }; } } } void ListaProduse::afisare() { if(nrProduse&gt;0) for(int i=0;i&lt;nrProduse;i++) { this-&gt;vector[nrProduse]-&gt;afisCamp(); } else cout&lt;&lt;"Nu exista produse in baza de date!"&lt;&lt;endl; } </code></pre> <p>Now I create in main an instance of ListaProduse. I call ListaProduse.adauga(filein) and then ListaProduse.afisare(). The problem is that when I call afisare() the program stop working and says: </p> <blockquote> <p>Unhandled exception at 0x00ba3055 in test.exe: 0xC0000005: Access violation reading location 0xcdcdcdcd.</p> </blockquote> <p>pointing to </p> <blockquote> <p>this->vector[nrProduse]->afisCamp();</p> </blockquote> <p>What could be the problem? Can anyone help me? Thanks!</p>
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    1. PO
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    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USIonut Ungureanu
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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      1. PTAnswer
    2. PO
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    3. PO
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    1. This table or related slice is empty.
    1. COPost what you have written in ListaProduse::afisCamp() ;
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      1. POCreate array of class objects inside another class
      1. USMahesh
    2. COThere is no ListaProduse::afisCamp(); There are only Cdvd::afisCamp(), CD::afisCamp() and DVD::afisCamp().
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      1. POCreate array of class objects inside another class
      1. USIonut Ungureanu
    3. COJust got confused with names while scrolling up and down ! Sorry
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      1. POCreate array of class objects inside another class
      1. USMahesh
 

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