Question

What is the best way of adding external files from a partial view?

I need to do something like this

code in partial view:

@{
    var files = new List<string>();
    files.Add("some path");
    files.Add("some path");
    ViewBag.Files = files;
}

in layout page

@foreach (var file in ViewBag.Files) {
    @file
}

this does not actually work though

Answer 1

As promised

You can’t render @section‘s as it’s not supported when rendered by Partial Views, until then you can do this trick:

in your _Layout.cshtml write

@RenderSection("scripts", false)
@Html.RenderSection("scripts")

The first one is the default, the second line is your brand new way to render a section, I use both in my code…

Now let’s add some code to our Partial View

instead of

@section scripts { 
   <script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
   <script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>
}

replace it with:

@Html.Section(
    @<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>, "scripts"
)
@Html.Section(
    @<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>, "scripts"
)

and our little helper that you just put inside your Models folder and reference it in your Partial View and Layout Page

// using idea from http://stackoverflow.com/questions/5433531/using-sections-in-editor-display-templates/5433722#5433722
public static class HtmlExtensions
{
    public static MvcHtmlString Section(this HtmlHelper htmlHelper, Func<object, HelperResult> template, string addToSection)
   {
      htmlHelper.ViewContext.HttpContext.Items[String.Concat("_", addToSection, "_", Guid.NewGuid())] = template;
      return MvcHtmlString.Empty;
   }

   public static IHtmlString RenderSection(this HtmlHelper htmlHelper, string sectionName)
   {
      foreach (object key in htmlHelper.ViewContext.HttpContext.Items.Keys)
      {
         if (key.ToString().StartsWith(String.Concat("_", sectionName, "_")))
         {
            var template = htmlHelper.ViewContext.HttpContext.Items[key] as Func<object, HelperResult>;
            if (template != null)
            {
               htmlHelper.ViewContext.Writer.Write(template(null));
            }
         }
      }
      return MvcHtmlString.Empty;
   }
}

To render CSS, all you need to so is using other section name, for example:

In _Layout.cshtml

@Html.RenderSection("styles")

in your Partial Views

@Html.Section(
  @<link rel="stylesheet" href="http://twitter.github.com/bootstrap/1.3.0/bootstrap.min.css">, "styles"
)

I hope this helps.