[Solved] TreeView BindTo Get Cannot use lamda expression error

[Aleksander]

So I have the following for my Tree

@{ Html.Telerik().TreeView().Name("tvContacts")
       .BindTo(ViewBag.Contacts, mappings =>
       {
           mappings.For<ContactSite>(binding => binding
               .ItemDataBound((item, site) =>
               {
                   item.Text = site.SiteName;
               })
               .Children(site => site.ContactGroups));
           mappings.For<ContactGroup>(binding => binding
               .ItemDataBound((item, group) =>
               {
                   item.Text = group.GroupName;
               })
               .Children(group => group.ContactPeople));
           mappings.For<ContactPerson>(binding => binding
               .itemDataBound((item, person) =>
               {
                   item.Text = person.FirstName + " " + person.LastName;
               }));
       });
}

Then I have the following for my objects

using System;
using System.Collections.Generic;
using System.Linq;

namespace OnCallTracker.Business
{
    public class ContactPage
    {
        public IEnumerable<ContactSite> ContactSites { get; set; }
    }

    public class ContactSites : List<ContactSite>
    {
    }

    public class ContactSite
    {
        public int SiteId { get; set; }
        public string SiteName { get; set; }
        public IEnumerable<ContactGroup> ContactGroups { get; set; }
    }

    public class ContactGroups : List<ContactGroup>
    {
    }

    public class ContactGroup
    {
        public int GroupId { get; set; }
        public string GroupName { get; set; }
        public string GroupDescription { get; set; }
        public ContactPerson Manager { get; set; }
        public IEnumerable<ContactPerson> ContactPeople { get; set; }
    }

    public class ContactPeople : List<ContactPerson>
    {
    }

    public class ContactPerson
    {
        public int PersonProfileId { get; set; }
        public Int64 PersonnelId { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string PersonnelName { get; set; }
        public string CellNumber { get; set; }
        public string DeskNumber { get; set; }

        public string GetContactPersonName()
        {
            return FirstName + " " + LastName;
        }
    }
}

Can you please tell me what I'm missing? I get the following error.

Server Error in '/' Application.

---

Compilation Error

Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: CS1977: Cannot use a lambda expression as an argument to a dynamically dispatched operation without first casting it to a delegate or expression tree type

Source Error:

Line 4: Line 5: @{ Html.Telerik().TreeView().Name("tvContacts") Line 6: .BindTo(ViewBag.Contacts, mappings => Line 7: { Line 8: mappings.For<ContactSite>(binding => binding

[Alex Gyoshev]

The error indicates that there is a syntax error in the lambda expression.

It seems that the last itemDataBound causes the issue -- it should be in PascalCase, ItemDataBound, like in the other mappings.

All the best,
Alex Gyoshev
the Telerik team

[Aleksander]

Ok I have changed this to PascalCase and I still get the same error. Anything else I'm missing?

[Alex Gyoshev]

Determine which of the mappings causes the error by using only one mapping at a time. Deleting most of the code will let you isolate the issue.

Also, make sure that the System.Data.Linq namespace is included in the view.

Greetings,
Alex Gyoshev
the Telerik team