asp.net mvc working without view file - asp.net-mvc

I have a plugable scenario on asp.net mvc. My Layout file contains a method for Head and body. Methods are rendering related plugin. So I have only one Controller/Action (Page/Index) and I dont need any view file for this action. Is that posible working without View file or only Layout file?
Thanks.
Layout example.
<html>
<head>
<title></title>
</head>
<body>
<div> MENU </div>
<div>
Plugin.Render("body"); //Render plugin method.
</div>
</body>
</html>

It seems an odd situation, but regardless:
It all depends on what you expect your one method to return. If it returns non-HTML (e.g. JSON, any primitive type, ...), you don't need it, obviously.
A HTML-layout is generally rendered via Views. I'm not sure if you can address your Master/Layout page as a view in and of itself. What I would suggest is adding a View file, setting it up with the correct Master/Layout page, and then basically empty out the view file.
So you'd have a View file, but it wouldn't have any content in it (except for the Master/Layout page setting).
It'd be slightly more understandable for future developers (although not that much), and I don't see any real downside to this (performance-wise or other).

Related

Set variable in layout and access it in template

I'm setting a variable in grails-app/views/layout/main.gsp to a value, like
<g:set var="welcometext" scope="session">Hello, pleased to meet you!</g:set>
But when I try to access it in my view grails/app/views/index.gsp with
<html>
<head>
<meta name="layout" content="main"/>
</head>
${welcometext}
<body>
</html>
Nothing gets printed out. So the variable set in main.gsp is not accessible to my view index.gsp. I tried also to set the scope to page, request and session, but success.
How can I set a variable in my layout main.gsp and reference it in other views?
You can define variables in your page (index) and your layout can see them (which is really useful for breadcrumb for example).
However, you can't access to a variable defined in your layout from your page (index) because the page is rendered like there was no layout, and then we apply the layout to the page rendered.
As a shortcut, you can see the rendering flow like this: (render Index) THEN (render Layout)
So, in your case, you have to find another solution, depending on your content:
Put the welcometext in session (not the best solution)
Pass it as a parameter of each view (not the best solution)
Create a custom tag to automatically print it
Create a template and render it where you need
Hardcode it ? (I don't like this one, but it's closer to what you're trying to do)
Use JavaScript to add the text ?
...
Try to see which one is the best for you ;)

Can I choose not to render a certain section in the layout page? [duplicate]

This question already has answers here:
Is it possible to make Razor sections optional?
(5 answers)
Closed 8 years ago.
I have an ASP.NET MVC layout page that is used by all the views in my application. Each of these views defines a "PanelRight" section, that is rendered in the layout page. However, now I would like to replace that section with some other markup. I thought it'd be as easy as commenting out the RenderSection instruction and adding my new markup, but I keep getting an exception ("The following sections have been defined but have not been rendered for the layout page").
I understand what the exception means; I only want to know how to get rid of it. Id est, can I NOT render a certain section that is defined in the views? Because I'd much rather not go through all of them and removing the section.
EDIT
I'll try to be more clear.
Suppose this is my layout page:
<html>
<head> <!-- HEAD STUFF --> </head>
<body>
#RenderSection("RightPanel", false)
#RenderBody()
</body>
</html>
and this is one of my many views:
#section RightPanel {
<div>This is the markup of the section</div>
}
<div>This is the body of my view</div>
Now I decide that, rather than having a RightPanel section that can be customized by each view, I want to have a fixed content instead. So I "remove" the section and replace it with the markup I want to use - straight into the layout (actually it will be in another partial, but not in a section, that's the point).
Of course, I don't want to go through all of my many views to delete the #section RightPanel { }. I just want the layout page to ignore the section. To make a comparison, it's like I defined a class with a DoFancyStuff() method, and then in the client code I never call that method. Not a problem there, so I see no reason why it would be here.
To recap: the view defines a section, the layout doesn't intend to render it. This results in an error. Is there a way to do this?
No, you cannot have a section in your view that your layout does not implement. This will result in a runtime error, and there's no way around that. The reason everyone is telling you how to implement optional sections is because the layout must implement any section any view might want to use, but, by making it optional, you can allow some views to use some sections while other views use other sections.
So, if I want to "comment out" a RenderSection, if just for a test, do I really have to go through all views and remove that section definition?
Technically, yes. Although you could simply wrap the section in regular HTML comments <!-- -->, so while it's rendered, it's rendered as an HTML comment instead of actual DOM elements. Also, with layout inheritance, you can sort of short circuit the views' sections by defining an empty section. For example:
_Layout.cshtml
#RenderSection("Foo")
_SubLayout.cshtml
#{ Layout = "~/Views/Shared/_Layout.cshtml"; }
#section Foo {}
SomeView.cshtml
#{ Layout = "~/Views/Shared/_SubLayout.cshtml"; }
#section Foo
{
<!-- stuff here -->
}
The section Foo would be empty because the sub-layout implements Foo but doesn't also call #RenderSection("Foo") itself, so there's no opportunity for a view using it as a layout to alter that section. That won't really help you now much, but it's good to know for future reference.
I suppose you could create a new layout with a different name and move the stuff from your current layout there while making your current layout inherit from the new layout. That would allow you to implement this without having to update all your layout references in your views. However, it will likely be easier to just to use HTML comments to comment out your section in your layout for testing purposes.
UPDATE
Just one more thing. Now that I'm thinking about it, the layout inheritance approach I suggested as one potential method, may actually not work. It occurred to me that you may still get an error because the sub-layout doesn't call #RenderSection. It all depends on whether the initial call in the main layout is enough to satisfy. HTML comments are definitely the safest and easiest approach.
UPDATE BY OP
Accepted answer:
you could simply wrap the section in regular HTML comments <!-- -->, so while it's rendered, it's rendered as an HTML comment instead of actual DOM elements.

How to hide a content placeholder if it has no children without client code (MVC)

I have a ContentPlaceholder inside of a MasterPageView. All of my other pages come from the same master and I have one page that needs about 70% of the behavior in this master. There is a navigation panel in the master that is spitting out un-necessary html even if left blank by the page. Looks like this:
<div class="span3">
<div class="side_navigation">
<ul>
<asp:ContentPlaceHolder ID="SideNavigation" runat="server" />
</ul>
</div>
</div><%-- /master sub-navigation --%>
I simply want to hide ALL of this markup whenever my placeholder (SideNavigation) has 0 children. I don't want to use javascript. I'd rather do this work on the server and deliver it to the client with less responsibility and markup. I've already tried doing "this.SideNavigation.Controls.Count" but it always ends up being 0. If there was a way I could tie into a loaded event and then test this logic that would be great. I am ok with making a code-behind file for my master, but it would be nice to be able to accomplish my goal in the .master file only.
Let me know what you think.
I would probably recommend using a different master page for the page without the navigation. You can have nested master pages so you don't necessarily need to duplicate code to do this.
However if you do wish to keep it like this, I would personally use a bit of javascript (with jquery) as follows
$(function(){
if($('.span3 .side_navigation ul li').length() == 0){
$('.span3').hide();
}
});
obviously i'd give span3 an ID to make it not hide every span3 but you hopefully get the idea.

CodeIgniter equivalents of ASP.NET MVC Master pages and content areas?

I used PHP years ago but have since been developing in C#/VB.Net.
In ASP.Net MVC 2, you can provide a master page which defines content areas eg:
<html>
<head>
<title>Overshare | <?=$Title?></title>
<ContentArea name="Head"/>
</head>
<body>
<ContentArea name="Body"/>
</body>
</html>
Your view would then have something like:
<Content name="Head">
<!-- Some Head Content -->
</Content>
<Content name="Body">
<h1>Some Body Here</h1>
</Content>
I don't seem to be able to emulate the same functionality with Code Igniter. The options seem to be:
manually pre-set some associative array of variables (eg in the controller) and then simply substitute the values into a template file - This is a lot of code to repeat in each view and doesn't belong in the controller. It also means it's a real pain to put large bodies of html into one of the ContentAreas - It's either string concatenation or something equally nasty with almost no chance of HTML intellisense in any IDE.
Use a templating library - I haven't found one which doesn't fundamentally work as described above
Now, I haven't used CodeIgniter before and am about to start a large PHP project so want to make sure it's the correct tool before actually starting work. Am I missing something obvious or is this templating functionality difficult to replicate?
Edit: Libraries tested:
Phil Sturgeon's Template Library
CI Smarty
PHXView
If you have a good idea of how your pages are to be built then you can write a set of functions to deal with it either in a MY_Controller.php file or in a library.
So you could have a routine which calls
$this->mypagetemplates();
Which calls data out of a class's properties eg $this->page->title;
I split my data as I create it into
$this->page->head,
$this->page->header,
$this->page->content,
$this->page->aside
$this->page->footer
Which corresponds with the HTML5 sections we use in 90% of our projects
My $this->mypagetemplates() function (or method if you prefer) can take a number of arguments and calls various views as a result eg:
$contentview = 'shop/products';
$asideview = 'shop/basket';
Which, if populated, are then called thus
If ($asideview) {
$this->load->view($asideview, $this->page->aside);
}
Overall Though, I'd say don't design your biggest ever project on a framework that us new to you. Play around first.
I ended up creating 3 files which represented the following
OpenHeader:
<html>
<head>
<Head Stuff/>
OpenBody:
</head>
<body>
<html>
<Templating Stuff>
Close:
</Templating Stuff>
</html>
</body>
</html>
And then modified my views to include these three at the appropriate time.
It's inelegant but flexible and powerful so it'll do for now - especially since I can pass varuables eg Page title into the files during the include if I use the CodeIgniter view engine to retrieve them

Embed ContentPlaceHolder between double quotes

I am using .NET MVC, and within view pages I set a contentplaceholder that contains an ID to be used on the master page like so:
View page:
<asp:Content ID="CDomBodyId" ContentPlaceHolderID="DomBodyId" runat="server">LmpDemoRequests</asp:Content>
Master page:
<body id='<asp:ContentPlaceHolder ID="DomBodyId" runat="server"></asp:ContentPlaceHolder>'>
So in this particular case, the body tag would render like this on the final HTML page:
<body id='LmpDemoRequests'>
I would like to have double quotes around the body id tag, but inverting the quotes like the following makes intellisense unable to find the contentplaceholder, giving me a lot of warnings when I compile.
<body id="<asp:ContentPlaceHolder ID='DomBodyId' runat='server'></asp:ContentPlaceHolder>">
Is there any way around this?
This is an issue with ASP.NET editor. It's not specific to MVC. I think the workaround is pretty good and I don't see a specific drawback.
Try declaring BodyID as a property of your MasterPage. Set its value in the View pages. Then you can do something like
<html>
<body='<%= BodyID %>'>
</body
</html>
Not sure if I have misunderstood your question, but you can also add:
<body id="site" runat="server"></body>
And then access it on your page
HtmlControl body = (HtmlControl)Master.FindControl("site");
body.Attributes.Add("class", "LmpDemoRequests");
I hope I understood your correctly.

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