Question

Are setters necessary for Collection Type Properties

//Type 1     class Company {     private IList<Customer> customers;      public IList<Customer> Customers     {         get { return customers; }         set { customers = value; }     } }   //Type 2   class Company  {        private readonly IList<Customer> customers = new List<Customer>();         public IList<Customer> Customers        {                get { return customers; }        }   } 

When do I use Type 1 vs Type 2 ? Wouldn’t it suffice if I initialize a List & use readonly property Customers ? as in Company.Customers.Add(new Customer)

What is the best practice with respect to providing setters for collection Type properties?

Answer 1

Please read the FxCop recommondation CAS2227 ‘Collection properties should be read only’ http://msdn.microsoft.com/en-us/library/ms182327(VS.80).aspx

it contains good advice 🙂