Implementing a Factory Pattern with CSLA.NET

Question

I would like to implement Factory Pattern in CSLA. I can use an abstract base class or an interface for the abstraction. I have decided to use an abstract class, only because I have certain common functionality such as, saving to store, retrieving from store, and deletion of the record. Also, some properties that would apply to all implemented objects.

C# only allows for inheritance from one class, so I can either use BusinessBase or the abstract class. I would also like the concrete types to have their own set of business rules. How can this be done with CSLA?

If I do what I have listed below, will the rules in both the abstract class as well as the concrete class get fired?

Some code ...

Abstract class:

public class Form : BusinessBase<Form> {
   private static PropertyInfo<string> FormNameProperty = RegisterProperty<string>(c => c.FormName);
   public string FormName
   {
      get { return GetProperty(FormNameProperty); }
   }

   public abstract void LoadContent();

   protected override void AddBusinessRules()
   {
      // business rules that are commmon for all implementations
   }
}

Concrete implementation:

public class FormA : Form {
   private static PropertyInfo<string> FirstNameProperty = RegisterProperty<string>(c => c.FirstName);
   public string FirstName
   {
      get { return GetProperty(FirstNameProperty); }
   }

   public override void LoadContent(){
      // some custom code
   }

   protected override void AddBusinessRules()
   {
      // business rules that only apply to this class
   }
}

Factory:

public static class FormFactory{
   public static Form GetForm(string formanmae) {
      Type formType = GetFormType(formName);
      if(formType == null)
         return null;

      var form = Activator.CreateInstance(formType) as ReferralForm;
         return form;
   }
}

Answer 1

Instead of using Activator.CreateInstance, you should use the Csla DataPortal.

var form = (Form)Csla.DataPortal.Create(formType, new Csla.Server.EmptyCriteria);

This way you are creating your business object using the Csla way, so any rules that should be run will be.