在.NET中使用域对象持续模式

public class Customer{    // 私有数据成员    String _customerId;    String _companyName;    String _contactName;    String _contactTitle;    public Customer() { }    // Customer对象的属性    public String CustomerId    {        get { return _customerId; }        set { _customerId = value; }    }    public String CompanyName    {        get { return _companyName; }        set { _companyName = value; }    }    public String ContactName    {        get { return _contactName; }        set { _contactName = value; }    }    public String ContactTitle    {        get { return _contactTitle; }        set { _contactTitle = value; }    }}public interface ICustomerFactory{    // 用于单行操作的标准事务方法    void Load(Customer cust);    void Insert(Customer cust);    void Update(Customer cust);    void Delete(Customer cust);    // 返回集合的查询方法    ArrayList FindCustomersByState(String state);}public class CustomerFactory : ICustomerFactory{    //用于单行操作的标准事务方法    void Load(Customer cust) { /* Implement here */ }    void Insert(Customer cust) { /* Implement here */ }    void Update(Customer cust) { /* Implement here */ }    void Delete(Customer cust) { /* Implement here */ }    //返回集合的查询方法    ArrayList FindCustomersByState(String state)    {        /* 此处是实现代码 */    }}

public class NorthwindApp{    static void Main(string[] args)    {        Customer cust = new Customer();        CustomerFactory custFactory = new CustomerFactory();        //从Northwind数据库载入客户        cust.CustomerId = "ALFKI";        custFactory.load(cust);        // 传递 Customer 对象        FooBar(cust);        // custList是Customer对象列表         ArrayList custList = custFactory.FindCustomersByState("CA");    }}