C++ Tutorial/Pointer/object pointer

array of pointers to objects

<source lang="cpp">#include <iostream>

 using namespace std;  
 class person{  
    protected:  
       char name[40]; 
    public:  
       void setName(){  
          cout << "Enter name: ";  
          cin >> name;  
       }  
       void printName()
       {  
          cout << "\n   Name is: " << name;  
       }  
   };  
 int main()  
   {  
    person* persPtr[100];
    int n = 0;           
    char choice;  
   
    do{  
       persPtr[n] = new person;         
       persPtr[n]->setName();           
       n++;                             
       cout << "Enter another (y/n)? "; 
       cin >> choice;                   
    }while( choice=="y" );                
   
    for(int j=0; j<n; j++){
       cout << "\nPerson number " << j+1;  
       persPtr[j]->printName();  
    }  
    cout << endl;  
    return 0;  
   }</source>

assign the address of a public member of an object to a pointer and then access that member by using the pointer

<source lang="cpp">#include <iostream> using namespace std;

class cl { public:

 int i;
 cl(int j) { i=j; }

};

int main() {

 cl ob(1);
 int *p;
  
 p = &ob.i; // get address of ob.i
  
 cout << *p; // access ob.i via p
  
 return 0;

}</source>

dereferencing the pointer returned by new

<source lang="cpp">#include <iostream>

 using namespace std;  
 class Distance                    
   {  
    private:  
       int feet;  
       float inches;  
    public:  
       void getdist() {  
          cout << "\nEnter feet: ";  
          cin >> feet;  
          cout << "Enter inches: ";  
          cin >> inches;  
       }  
       void showdist(){
          cout << feet << "\"-" << inches << "\""; 
       }  
   };  
 int main(){  
    Distance& dist = *(new Distance);  
                                       
    dist.getdist();                    
    dist.showdist();                   
    cout << endl;  
    return 0;  
   }</source>

Pointers to Objects

<source lang="cpp">#include <iostream> using namespace std;

class cl {

 int i;

public:

 cl(int j) { i=j; }
 int get_i() { return i; }

};

int main() {

 cl ob(88), *p;
  
 p = &ob; // get address of ob
  
 cout << p->get_i(); // use -> to call get_i()
  
 return 0;

}</source>

uses a pointer to access all three elements of array ob after being assigned ob"s starting address

<source lang="cpp">#include <iostream> using namespace std;

class cl {

 int i;

public:

 cl() { i=0; }
 cl(int j) { i=j; }
 int get_i() { return i; }

};

int main() {

 cl ob[3] = {1, 2, 3};
 cl *p;
 int i;
  
 p = ob; // get start of array
 for(i=0; i<3; i++) {
   cout << p->get_i() << "\n";
   p++; // point to next object
 }
  
 return 0;

}</source>