I would raise that as a bug, should be handling a null exception :). It feels like that record is not there or has been deleted from the database.

Charlie

Does this happen for a specific record or all records? And on all forms or on a specific form? 

It happens for all records on specific forms. But not all forms seems to be affected. I don't know all mutations the user did on those affected forms.

Ok thanks for the details, would it be possible to send a backup of the site to tg at umbraco dot com then I can debug and fix the issue since I can't reproduce atm

Seems I didn't test my customized field-type in the backend. What I miss to implement, that user can also edit records in the backend?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web.UI;
using System.Web.UI.WebControls;
using Umbraco.Forms.Core;
using Umbraco.Forms.Core.Attributes;
using Umbraco.Forms.Core.Providers.FieldTypes;

namespace easyPush.Contour.CustomFieldType
{
    /// <summary>
    /// Label field.
    /// </summary>
    public class Label : FieldType
    {
        private MarkdownSharp.Markdown markdown = new MarkdownSharp.Markdown();

        [Setting("Text", description = "Enter text as HTML", control = "Umbraco.Forms.Core.FieldSetting.TextArea")/**, assembly = "easyPush.Contour", control = "easyPush.Contour.FieldSetting.UnvalidatedTextArea")**/]
        public string Text { get; set; }

        public Label()
        {
            Id = new Guid("42E2850C-E6FB-439C-B04B-3E36C6DE2CDF");
            Name = "Label";
            Description = "This is a static text. Please enter your text in Markdown.";
            Icon = "textarea.png";
        }

        public override string RenderPreview()
        {
            return markdown.Transform(Text);
        }

        public override string RenderPreviewWithPrevalues(List<object> prevalues)
        {
            return markdown.Transform(Text);
        }

    }
}

FieldType.Label.cshtml

@model Umbraco.Forms.Mvc.Models.FieldViewModel
<div class="formText">
@if (Model.AdditionalSettings.FirstOrDefault(x => x.Key == "Text") != null)
{
    var md = new MarkdownSharp.Markdown();

    @Html.Raw(md.Transform(Model.AdditionalSettings.FirstOrDefault(x => x.Key == "Text").Value))
}
</div>

Ok looked a bit more in the issue, moving the edit away from webforms will be something we'll do for version 4, so the option you have now is to add the following to your fieldtype 

publicoverride System.Web.UI.WebControls.WebControl Editor { get { System.Web.UI.WebControls.Panel pnl = new System.Web.UI.WebControls.Panel(); pnl.ID = "pnlHolder";string actualText = ParseTokens(TextToShow); var md =newMarkdownSharp.Markdown();
 pnl.Controls.Add(new System.Web.UI.LiteralControl(md.Transform(Text)));

return pnl; } set { base.Editor = value; } } publicoverride List<object> Values { get { Value.Clear(); Value.Add(string.Empty); return Value; } set { Value = value; } }

Thank you very much!

After implementing the editor property everything works now.

Best regards.

Now everything solved.

In the other custom field types I inherit from your field types (TextField, CheckBox etc.) - so everything was implemented. But especialy for this Field-Type I used your abstract class, and because Editor is marked virtual everything compiled but during runtime, there wasn't any implementation.

I hope everything can be migrated to Razor, so I don't have to deal with webforms.

Great, glad for confirming it works :)

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