Sounds like it's not a large control, can you post the code behind and html  source for your user control? Might save some of the back and forth questions.

-Chris

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="NodenameByQs.ascx.cs" Inherits="UmbracoCustomDatatypeNodenameByQs.NodenameByQs" %>
<asp:Label ID="Label1" runat="server" Text=""></asp:Label>
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using umbraco.presentation.nodeFactory;

namespace UmbracoCustomDatatypeNodenameByQs
{

    public partial class NodenameByQs : System.Web.UI.UserControl, umbraco.editorControls.userControlGrapper.IUsercontrolDataEditor
    {
        public string umbracoValue;
        public int nodeid;
        Node mynode;

        protected void Page_Load(object sender, EventArgs e)
        {

            if (!String.IsNullOrEmpty(Request.QueryString["id"]))
            {
                nodeid = int.Parse(Request.QueryString["id"]);
                mynode = new Node(nodeid);

                Label1.Text = mynode.Name;
            }
        }

        public object value
        {
            get
            {
                return umbracoValue;
            }
            set
            {
                umbracoValue = value.ToString();
            }
        }
    }
}

Hi guys!

Has anybody solved this problem ? I'm facing the same situation here.

Thanks

Sergio Nunes

I was having this same issue. After digging into it a bit I found that the Doc2Form.cs was calling the set method of my custom datatype and passing it a null value. This, of course, throws the dreaded 'Null Reference Exception' in the set method when using "value.ToString()'. However the error gets suppressed by a try/catch block. So it doesn't tell you what the error is. It just quits building the form.

Fortunatelyl, the fix for this is very easy. In the 'Set' method of any custom datatype, check the 'value' for null and set a default value if null is passed. Here's an example of my 'Value' property from my custom datatype.

        public object value
        {
            get
            {
                myvalue = string.Empty;

                foreach (ListItem item in ddlmyvalues.Items)
                {
                    if (item.Selected)
                        myvalue = item.Value;
                }
                return myvalue;
            }
            set
            {
                if (value == null) value = string.Empty;
                myvalue = value.ToString();
            }
        }

I hope this helps anyone else out there having the same problem. If you find that it solves your problem please mark this post accordingly. Also a High Five would be much appreciated.

Happy coding fellow Umbracians.

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