List not returned from RIA Service-优快云博客

http://forums.silverlight.net/forums/p/111734/304586.aspx

List<> not returned from RIA Service

07-17-2009 11:06 AM |

I have a simple object (Person) defined in my Sample1.Web project:

    public class Person
    {
        [Key]
        public int Id { get ; set ; }

        public string FirstName { get ; set ; }

        public string LastName { get ; set ; }

        public IList Children { get ; set ; }
    }

and a simple in-memory data store (PersonData) also defined in the same project:

    public class PersonData
    {
        private List people = new List
        (
            new Person[]
            {
              new Person()
              {
                  Id = 1,
                  FirstName = "Homer" ,
                  LastName = "Simpson" ,
                  Children = new List()
                  {
                      new Person()
                      {
                          Id = 3,
                          FirstName = "Lisa" ,
                          LastName = "Simpson"
                      },
                      new Person() { Id = 4, FirstName = "Bart" ,
                          LastName = "Simpson"
                      }
                  }
              },
              new Person()
              {
                  Id = 2,
                  FirstName = "Peter" ,
                  LastName = "Griffin" ,
                  Children = new List()
                  {
                      new Person()
                      {
                          Id = 5,
                          FirstName = "Chris" ,
                          LastName = "Griffin"
                      },
                      new Person()
                      {
                          Id = 6,
                          FirstName = "Meg" ,
                          LastName = "Griffin"
                      }
                  }
              }
            }
        );
        public IList People { get { return this .people; } }
    }

Finally, in the same Sample1.Web project, I have a Domain Service (PersonService) defined:

    [EnableClientAccess()]

    public class
 PersonService : DomainService

    {

        private
 PersonData personData = new
 PersonData();



        public
 IEnumerable GetPeople()

        {

            return this
.personData.People;

        }

    }

In the client project (Sample1), I have the following code defined in MainPage.xaml.cs:

        private
 PersonContext context = new
 PersonContext();

        public
 MainPage()

        {

            InitializeComponent();



            object
 state = null
;

            LoadOperation loadOp = this
.context.Load(this
.context.GetPeopleQuery(), TreeLoadedCallback, state);

            this
.MyTree.ItemsSource = loadOp.Entities;

        }



        private void
 TreeLoadedCallback(LoadOperation op)

        {

            if
 (!op.HasError)

            {

                object
 state = op.UserState;

                MyTree.ItemsSource = op.Entities;  // 'Children' attribute is always null here!!!!

            }

            else


            {

                throw new
 Exception(op.Error.Message);

            }

        }

My problem is that the "Children" attribute in the entities returned are always null. They are, of course, populated on the server. However, they are always null on the client. Any help is much appreciated.

Thanks.

ColinBlair

All-Star

16883 points

2,924 Posts

Re: List<> not returned from RIA Service

07-17-2009 11:21 AM |

    public class Person
    {
        [Key]
        public int Id { get ; set ; }

        public string FirstName { get ; set ; }

        public string LastName { get ; set ; }
        [Include]
        public IList Children { get ; set ; }
    }