如何使用泛型将此方法放在父类中？

Question

我有许多复数项目类,每个类都有一个单一项目类的集合,如下所示:

public class Contracts : Items
{
        public List<Contract> _collection = new List<Contract>();
        public List<Contract> Collection
        {
            get
            {
                return _collection;
            }
        }
}

public class Customers: Items
{
        public List<Customer> _collection = new List<Customer>();
        public List<Customer> Collection
        {
            get
            {
                return _collection;
            }
        }
}

public class Employees: Items
{
        public List<Employee> _collection = new List<Employee>();
        public List<Employee> Collection
        {
            get
            {
                return _collection;
            }
        }
}

我可以想象我可以使用泛型将它放到父类中.我怎么能这样做,我想它看起来像这样:

伪代码:

public class Items
{
        public List<T> _collection = new List<T>();
        public List<T> Collection
        {
            get
            {
                return _collection;
            }
        }
}

Answer 1

这是完全正确的,除了你还想要一个<T>后项目:

public class Items<T>
{
        public List<T> _collection = new List<T>();
        public List<T> Collection
        {
            get
            {
                return _collection;
            }
        }
}

要实例化:

Items<Contract> contractItems = new Items<Contract>();

Answer 2

是的,虽然物品也必须是通用的.

public class Items<TItem>
{
    private IList<TItem> _items = new List<TItem>();
    public IList<TItem> Collection
    {
        get { return _items; }
    }
    // ...
 }

让Items继承也许是有意义的IEnumerable<TItem>.