how can I call method class list

[abab]

If I have class with static field:

public class Cart
{
        private static int quantity_all_books = 0; 

        public int id { get; private set; }
        public int quantity { get; private set; }

        public Cart(int x, int y)
        {
            quantity_all_books++;

            id = x;
            quantity = y;
        }
}

And I have list type of this class:

List<Cart> shopping = new List<Cart>();
shopping.Add(new Cart(53, 2));
shopping.Add(new Cart(44, 1));

How can I check value static field quantity_all_books. I have tried make this field public, write method which return value of this field. But when I write "shopping." Visual Studio don't give me on the list this field or method.

[darwen]

Have a static property e.g.

public class Cart
{
        private static int quantity_all_books = 0; 

        public static int QuantityAllBooks
        {
                get { return quantity_all_books; }
        }
}

You gain access to static methods not by specifying them on an instance, but this way :

int quantityAllBooks = Cart.QuantityAllBooks;

Darwen.

[abab]

thx very much

[JonnyPoet]

thx very much

Excuse my question, but is there a specific reason to have this field quantity_all_books static ? Whats the reason behind that ?

[boudino]

Yes, it strange. I think that better approach would be to read Count property of a collection where instances of Cart are stored, because without a storage, it doesn't make sence to count them.

[JonnyPoet]

public class Cart
{
        private static int quantity_all_books = 0; // unnecessay here
       .....
}

What do you want to count ? Books ? Ok what do they have to do with Cart ? You are collecting Cart in a list so you have a Count property all the times So why not simple

List<Cart> shopping = new List<Cart>();
shopping.Add(new Cart(53, 2));
shopping.Add(new Cart(44, 1));
// now counting
int amount = shopping.Count;

It's totally unusual design to have the amount of Chart classes as a propety of that Cart class itself.

I would create a Carts class which contains all books. My rule is : Classes which ends with plural 's ' are collections of classes which have the same but singular name. Product, Products, Book, Books...
This way

public class Carts{
    private  List<Cart> shopping;
  // Constuctor
  public Carts(){
      shopping = new List<Cart>();
  }
  // Properties
   public int Count{
      get { return shopping.Count;}
  }
  // methods
  public void Add(Cart cart){
      shopping.Add(cart);
  }
}

Overthing your design.