C++ Array of Objects - Declare and Initialize

In this C++ tutorial, you will learn how to declare and initialize an array of objects. We shall discuss two ways in which we create an array of objects, with examples.

C Array of Objects

You can store objects of user defined datatype in a C++ Array.

To store objects of user defined datatype in an array, you can declare an array of the specific type and initialize the array just like an array of ints.

1 Array of Objects Declare and Initialize Separately

In the following example, we shall declare an array of type Student, with size of five. Student is a class that we defined in the program. Then we shall assign objects using index of array.

C++ Program

#include <iostream>
using namespace std;

class Student {
   public:
   string name;
   int rollno;

   Student() {}

   Student(string x, int y) {
      name = x;
      rollno = y;
   }

   void printDetails() {
      cout << rollno << " - " << name << endl;
   }
};

int main() {
   //declare array with specific size
   Student students[5];
   
   //assign objects
   students[0] = Student("Ram", 5);
   students[1] = Student("Alex", 1);
   students[2] = Student("Lesha", 4);
   students[3] = Student("Emily", 3);
   students[4] = Student("Anita", 2);

   for(int i=0; i < 5; i++) {
      students[i].printDetails();
   }
}

Output

5 - Ram
1 - Alex
4 - Lesha
3 - Emily
2 - Anita

2 Array of Objects Declare and Initialize in a Single Line

In the following example, we shall declare an array of type Student, and initialize the array with objects of Student type in a single line.

C++ Program

#include <iostream>
using namespace std;

class Student {
   public:
   string name;
   int rollno;

   Student() {}

   Student(string x, int y) {
      name = x;
      rollno = y;
   }

   void printDetails() {
      cout << rollno << " - " << name << endl;
   }
};

int main() {
   //declare array with specific size
   Student students[] = {Student("Ram", 5), Student("Lesha", 4), Student("Anita", 2)};
   
   for(int i=0; i < 3; i++) {
      students[i].printDetails();
   }
}

Output

5 - Ram
4 - Lesha
2 - Anita

Conclusion

In this C++ Tutorial, we learned how to initialize an array of custom class type objects, with example C++ programs.