Send a class object between Web Parts

Question

I am having some difficulty transmitting a class object between two web parts (Provider and Consumer). Basically whenever I try to build my project I get this error:

'ConnectableWebParts.LinkButtonProvider.LinkButtonProvider' does not implement interface member 'ConnectableWebParts.ISalObject.SalItem'

I have achieved this using primitive objects such as strings, but for some reason it has problems with transmitting a class that has 3+ string variables.

I have looked over some of my previous examples to see if there is something I am missing, but it all looks correct. So I assume there is some unique difference between transferring primitive objects and transferring class objects.

Could really use a second pair of eyes, or if someone has done this before that would be great. Thank you for your time.

Solution below.

Interface

namespace ConnectableWebParts
{
    public interface ISalObject
    {
        SalObject SalItem { get; set; }
    }
}

Class

namespace ConnectableWebParts
{
    public class SalObject
    {
        private string name;
        private string description;
        private string code;

        public string Name { get { return name; } set { name = value; } }
        public string Description { get { return description; } set { description = value; } }
        public string Code { get { return code; } set { code = value; } }

        public SalObject() {
            name = "";
            description = "";
            code = "000000";
        }

        public void storeDate()
        {
            Name = "John Doe";
            Description = "Good Omen";
            Code = "111111";
        }
    }
}

Provider

namespace ConnectableWebParts.LinkButtonProvider
{
    [ToolboxItemAttribute(false)]
    public partial class LinkButtonProvider : WebPart, ISalObject
    {
        private SalObject _salvage = new SalObject();

        [Personalizable()]
        public SalObject Salvage {
            get { return _salvage; }
            set { _salvage = value; }
        }

        [ConnectionProvider("Provider for SalObject From LinkButton", "SalObjectProvider")]
        public ISalObject SalObjectProvider()
        {
            return this;
        }

        public LinkButtonProvider()
        {
        }

        protected override void OnInit(EventArgs e)
        {
            base.OnInit(e);
            InitializeControl();
        }

        protected void Page_Load(object sender, EventArgs e)
        {
        }

        protected void LinkButton1_Click(object sender, EventArgs e)
        {
            Salvage = new SalObject();
        }
    }
}

Consumer

namespace ConnectableWebParts.LinkButtonConsumer
{
    [ToolboxItemAttribute(false)]
    public partial class LinkButtonConsumer : WebPart
    {
        private ISalObject _myProvider;

        [ConnectionConsumer("SalObject Consumer", "SalObjectConsumer")]
        public void SalvageConsumer(ISalObject Provider)
        {
            _myProvider = Provider;
        }

        public LinkButtonConsumer()
        {
        }

        protected override void OnInit(EventArgs e)
        {
            base.OnInit(e);
            InitializeControl();
        }

        protected void Page_Load(object sender, EventArgs e)
        {
        }

        protected override void OnPreRender(EventArgs e)
        {
            EnsureChildControls();
            if (_myProvider != null)
            {
                NameCell.Text = _myProvider.SalItem.Name;
                DescCell.Text = _myProvider.SalItem.Description;
                CodeCell.Text = _myProvider.SalItem.Code;
            }
        }
    }
}

EDIT: Haha hah!

Turns out when dealing with class objects I don't even need to use an Interface.
It would seem an interface is required when dealing with primitive objects (string, int, long, etc.) or OOTB Web Parts.

So I just removed the interface from the project, replaced all my calls to the class name itself, and set my Provider to only inherit from WebPart.

Now it works exactly like I wanted it to. I hope other people can use this information.

Answer 1

I might be totally off on this but I think you would have to make sure your object (class) supports serialization.

Basic serialization would require marking the class with the [Serializable] attribute but you might need something more advanced. See here for more details: http://msdn.microsoft.com/en-us/library/4abbf6k0%28v=vs.90%29.aspx

In any case using basic serialization would be quick enough to try.

Answer 2

Haha hah!

Turns out when dealing with class objects I don't even need to use an Interface.
It would seem an interface is required when dealing with primitive objects (string, int, long, etc.) or OOTB Web Parts.

So I just removed the interface from the project, replaced all my calls to the class name itself, and set my Provider to only inherit from WebPart.

Now it works exactly like I wanted it to. I hope other people can use this information.