how to new a vector c++ class code example

Example 1: make a vector of an objects c++

#include <vector>
using std::vector;

class MyClass { .... };

vector<MyClass> myVector( 100, MyClass() );
/* myVector now contains 100 objects of type MyClass, built with the default constructor */

vector<MyClass> myVector2;
// MyVector2 is empty

myVector2.assign( 100, MyClass() );

// My Vector2 now contains 100 objects of type MyClass, built with default ctor

Example 2: vector in c++ class

#include <iostream>
#include <vector>

class Object
{
	public:
		Object()
		{}
		~Object()
		{}
		void AddInt(int num)
		{
			m_VectorOfInts.push_back(num);
		}
		std::vector<int> GetCopyOfVector()
		{
			return m_VectorOfInts;
		}
		void DisplayVectorContents()
		{
			for( unsigned int i = 0; i < m_VectorOfInts.size(); i++ )
			{
				std::cout << "Element[" << i << "] = " << m_VectorOfInts[i] << std::endl;
			}
			std::cout << std::endl;
		}

	private:
		std::vector<int> m_VectorOfInts;
};

int main()
{
	// Create our class an add a few ints
	Object obj;
	obj.AddInt(32);
	obj.AddInt(56);
	obj.AddInt(21);

	// Display the vector contents so far
	obj.DisplayVectorContents();

	// Creates a copy of the classes container you can only really view whats in 
	// the classes vector container. What ever changes you make here wont effect the class.
	std::vector<int> container1 = obj.GetCopyOfVector();
	// These elements wont be added as it's a copy of the container
	container1.push_back(342);
	container1.push_back(64);
	container1.push_back(123);


	// Display the classes container to see show nothing was added.
	obj.DisplayVectorContents();

	return 0;
}

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Cpp Example