FieldRenderer.Render for controller Rendering not "working"

Question

I am trying to create a controller Rendering with the use of FieldRenderer.Render, but this does not work.

The Controller

public ActionResult PageImage()
{
        return View(PageImageModelBuilder.GetPageImageViewModel(RenderingContext.Current.ContextItem));
}

the function where I am building my ViewModel

   public PageImageViewModel GetPageImageViewModel(Item currentItem)
    {
        var model = new PageImageViewModel();
        try
        {
            var renderer = new FieldRenderer();
            renderer.DisableWebEditing = false;
            renderer.Item = currentItem;
            renderer.FieldName = "Image";

            model.PageImage = new HtmlString(renderer.Render());
            //model.PageImage = new HtmlString(FieldRenderer.Render(currentItem, "Image"));
            model.Beschreibung = new HtmlString(FieldRenderer.Render(currentItem, Templates.PageImage.Fields.Beschreibung_FieldName));
        }
        catch (Exception exception)
        {
            Sitecore.Diagnostics.Log.Error("GetPageImageViewModel Error", exception, typeof(PageImageViewModel));
        }

        return model;
    }

the view Model

public class PageImageViewModel
{
    public HtmlString PageImage { get; set; }
    public HtmlString Beschreibung { get; set; }
}

and last but not Least the Controller Rendering

@using Feature.PageContent
@model Feature.PageContent.Models.Models.PageImageViewModel

<div class="">
  <p>Hallo Welt</p>
  @Model.PageImage
  <p>Sitecore()Field:</p>
  @Html.Sitecore().Field("Image", new { mw = 400, @class = "img-fluid" })
  <p>FieldRenderer: 
     @Model.Beschreibung
  </p>
  <p>Default Field: @Html.Sitecore().Field("Beschreibung")</p>
 </div>

The Renderings with "Sitecore().Field" are working, but my controller Renderings with HTmlString are not showing up

I think I am doing something wrong with the Context perhaps but I am not shure what. When you need more informations then plz tell me.

Is using a ViewModel with HtmlString the right approach or what should I use?

Answer 1

It seems that I was using the wrong Context Item when I use this

RenderingContext.Current.Rendering.Item

everything is working fine. Would be nice to know what is the difference between these two contexts