HTML Helper in C# to prevent FOUC in Knockout

BeginKnockoutLoadingContainerWriter.cs

namespace MyNamespace.Knockout
{
  public class BeginKnockoutLoadingContainerWriter : IDisposable
  {
    protected ViewContext _viewContext;
  
    public BeginKnockoutLoadingContainerWriter(ViewContext context)
    {
      if (context == null)
        throw new ArgumentNullException("context");
  
      _viewContext = context;
  
      // Write the html
      _viewContext.Writer.Write("<div>");
      _viewContext.Writer.Write("<div data-bind='visible: false'>");
      _viewContext.Writer.Write("Loading <img src='/assets/img/ajax-loader.gif' alt='Loading Spinner'/>");
      _viewContext.Writer.Write("</div>");
      _viewContext.Writer.Write("<div style='display:none' data-bind='visible: true'>");
  
      return;
    }
  
    public void Dispose()
    {
        _viewContext.Writer.Write("</div></div>");
    }
  }
  
  public static class LayoutHelpers
  {
    public static BeginKnockoutLoadingContainerWriter BeginKnockoutLoadingContainer(this HtmlHelper html)
    {
      return new BeginKnockoutLoadingContainerWriter(html.ViewContext);
    }
  }
}

fouc_html_example.html

<div>
  <div data-bind='visible: false'>
    Loading <img src='loading.gif' alt='Loading Spinner'/>
  </div>
  <div style='display:none' data-bind='visible: true'>
    <!-- Your content -->
  </div>
</div>

index.cshtml

@using MyNamespace.Knockout

@using (Html.BeginKnockoutLoadingContainer()) {
	<!-- Your content -->
}