13

So I have a Layout page

<head>
    @RenderSection("HeaderLast", required: false)
</head>

A view

@section HeaderLast
{
    <script src="@Url.Content("~/Scripts/knockout-1.2.0.js")"
                            type="text/javascript"></script>
}

<div id="profile-tab">
        @{ Html.RenderPartial("_userProfile"); }
</div>

And a Partial view

@section HeaderLast
{
    <script type="text/javascript">
        alert('test');
    </script>
}

<div......

I figured it couldn't be that simple. Is there a proper way to do this out of box or will this always require some kind of mediator and passing stuff around ViewData to manually make the content bubble up to the layout page?

Bounty started: The bounty will be rewarded to the best solution provided for this short coming. Should no answers be provided I will award it to @SLaks for originally answering this question.

Chris Marisic
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  • the section needs to be defined in the actual page for the framework to know it's been taken care of no? –  May 12 '11 at 16:57
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    I don't understand the question - what are you trying to do, and what are you trying to eliminate? – Danny Tuppeny May 12 '11 at 16:57
  • @cvista the section is defined in the LayoutPage because that's where the header is. @Danny Tuppeny I want to access the header from the partial view – Chris Marisic May 12 '11 at 17:13
  • i dont mean defined - i mean implemented - your @section is in the ctrl –  May 12 '11 at 17:21
  • @Chris Marisic, did you find the solution for this? I have the same situation to handle – Prasad May 17 '11 at 13:57
  • @Prasad I have not yet, I threw a bounty on this question and hopefully we'll see some interesting ideas/projects shaken out of it. For the time being in my personal project I just embedded the javascript inline for now /shrug. – Chris Marisic May 17 '11 at 14:10

5 Answers5

8

You cannot define sections in partial views.

Instead, you can put the Javascript in ViewBag, then emit any Javascript found in ViewBag in the layout page.

SLaks
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  • Anyone make a nuget for this yet? it's a rather glaring design shortcoming. – Chris Marisic May 12 '11 at 17:18
  • @Chris - Why do you think it is a glaring design shortcoming? – JasCav May 12 '11 at 17:25
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    @JasCav: If a partial needs its own CSS, it has no good way to get it rendered. – SLaks May 12 '11 at 17:26
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    I agree with Chris and SLaks, this is rather annoying. I'd like to be able to develop partial views in a modular fashion with their own css and js, and have a mechanism in rendering the partial view take care of placing the css and js into the DOM correctly. SLaks, is there an example of your solution somewhere? – Patrick Lee Scott Jul 08 '11 at 21:37
6

@JasCav: If a partial needs its own CSS, it has no good way to get it rendered.

If that's the reason for its use, it could very well be by design.

You don't want to have a separate CSS file x partial/helper. Remember, each separate CSS file means a separate request to get it from the server, thus an additional round-trip that affects time to render your page.

Also you don't want to emit direct CSS to the HTML from the partial/helper. Instead you want it to have appropriate hooks you can use to define all the look in your site's CSS file.

You can use the same hooks you have available for CSS to activate custom JavaScript behaviors for the elements involved When JavaScript is enabled.

Finally it may be the case what you need is not a Partial View, but an extra Layout you use for some pages. With that approach you would have:

  • A master Layout that gets set automatically on _ViewStart like you probably has now. This defines the sections like in your sample.
  • A children Layout page. Here you have both the extra html, css, js you need to have for these views. This uses both @RenderBody() and @section SomeSection { } to structure your common extra layout.
  • Some views that point to the children layout, and others that use the default master layout.

How to get extra data to the children Layout is out of the scope of the question, but you have several options. Like having a common base for your entities; using ViewBag or calling Html.RenderAction to get that shared logic related to shared dynamic elements in the layout.

eglasius
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  • Using the multiple layout pages for this seems like it would be an exercise in nightmare maintenance. – Chris Marisic May 20 '11 at 16:07
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    I've used the approach and it has flowed nicely as code evolves. The specific way I've done it is "calling Html.RenderAction to get that shared logic related to shared dynamic elements in the layout.". I very much prefer it over having a partial view do a Html.RenderAction; having to deal with extra data in unrelated actions for it to flow to the partial views or using an untyped approach to pass the data. Your sample is too generic so is hard to tell, challenge the notion of that piece belonging in a partial view / maybe is really part of some common layout. – eglasius May 20 '11 at 16:19
  • Note real partial views usually fall in the first scenarios in my answer, so also challenge whether that script/css should be called from that partial view vs. belonging to site level css/js files that hooks into it. That said, there are just too many scenarios out there, you may have a case where doing what you are trying to do is the best approach. – eglasius May 20 '11 at 16:22
  • It's independent to this question but I'm starting to consider doing something semi-revolutionary by considering actually using true views to be javascript files so there is always view.cshtml and view.js.cshtml and then writing all component javascript as partial views or sections inside of a partial view and using render partial inside my js views. I'm leaning on seeing if I can figure out a way to have a partial view that defines a section and to render that inside the js view so my widget type components are all self contained and just need hoisted into view and view.js. – Chris Marisic May 20 '11 at 17:15
  • Another thought on that would be to remove the need for a separate view.js.cshtml and actually define a javascript section in my view and then figure out how to serve the content of that section for `script src="view.js"`. – Chris Marisic May 20 '11 at 17:16
1

It looks like there was a similar question on SO - How to render JavaScript into MasterLayout section from partial view?.

Unfortunately, there is no possibility of declaring sections inside Partial Views. That is because RenderPartial ends up rendering totally separate view page. There is a workaround to this, though a bit ugly. But it can look better if using strongly-typed model instead of ViewData.

Basically, you need to keep track of the reference to the view which called RenderPartial and use the DefineSection method on the object passed to push data to that view.

UPDATE: There is also a blog post about dealing with RenderSection you may find useful.

Community
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Piotr Szmyd
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1

Here is another approach using helper methods and templated delegate http://blogs.msdn.com/b/marcinon/archive/2010/12/15/razor-nested-layouts-and-redefined-sections.aspx

Eugene Agafonov
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0

As a follow up to my question, the JavaScript/CSS combiner/minifier tool Cassette supports this functionality to allow you to compartmentalize your JavaScript and other assets that are required for partials.

I purchased a site license and use this in all of my MVC applications now.

Chris Marisic
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