Introduction

There are various types of collections or collections. An array-based list is one whose count is known in advance. For example, a array-based collection of 10 cars contains 10 cars, may-be less but not more.

To use a collection as an entity, you can create a class for it; this class would be used to add items in the collection, to remove items in the list, or to perform other necessary operations. You can start from a simple class as follows:

public ref class CCollection
{
};

After creating the class for a collection, the collection becomes an object and its class can be used like any other. This means that, before the collection, you can declare a variable for it here is an example:

using namespace System;

public ref class CCollection
{
};

int main()
{
    CCollection ^ list = gcnew CCollection;

    return 0;
}

For an array-based list, because you must specify the number of items that the list will contain, you can declare an array as a member variable. Here is an example:

public ref class CCollection
{
private:
    // This collection will be a list of decimal numbers
    static array<double> ^ Item = gcnew array<double>(20);

public:
    // Our default constructor, used to initialize the collection
    CCollection()
    {
    }
}

Although you can initialize a static array in a C++ class, remember that you can also use a constructor to initialize it. Here is an example:

using namespace System;

int MaxCount = 20;

public ref class CCollection
{
private:
    // This collection will be a list of decimal numbers
    array<double> ^ Item;

public:
    CCollection();
};

CCollection::CCollection()
{
    Item = gcnew array<double>(MaxCount);
}

A primary accessory you need when using a list is a count of the number of items in the list when they are added or deleted. This accessory is primarily a private field as a simple natural number. When the class is declared, this member variable should be set to 0 to indicate that the list is primarily empty:

int MaxCount = 20;

public ref class CCollection
{
private:
    // This collection will be a list of decimal numbers
    array<double> ^ Item;


private:
    // This is the size of the collection
    int size;

public:
    CCollection();
};

CCollection::CCollection()
{
    Item = gcnew array<double>(MaxCount);
    size = 0;
}

Since the size member variable was declared private, if you plan to get the count of items in the list from outside the class, you can provide a property to take care of this-> This can simply be done as follows:

using namespace System;

int MaxCount = 20;

public ref class CCollection
{
private:
    // This collection will be a list of decimal numbers
    array<double> ^ Item;

private:
    // This is the size of the collection
    int size;

public:
    // This represents the number of items in the collection
    property int Count
    {
        int get() { return size; }
    }

public:
    CCollection();
};

CCollection::CCollection()
{
    Item = gcnew array<double>(MaxCount);
    size = 0;
}

int main()
{
    CCollection ^ list = gcnew CCollection;

    Console::WriteLine(L"Number of Items: {0}", list->Count);

    return 0;
}

This would produce:

Number of Items: 0
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