Html.ActionLink in Partial View - asp.net

I am using the following code in my master page:
<% Html.RenderAction("RecentArticles","Article"); %>
where the RecentArticles Action (in ArticleController) is :
[ChildActionOnly]
public ActionResult RecentArticles()
{
var viewData = articleRepository.GetRecentArticles(3);
return PartialView(viewData);
}
and the code in my RecentArticles.ascx partial view :
<li class="title"><span><%= Html.ActionLink(article.Title, "ViewArticle", new { controller = "Article", id = article.ArticleID, path = article.Path })%></span></li>
The problem is that all the links of the articles (which is built in the partial view) lead to the same url- "~/Article/ViewArticle" .
I want each title link to lead to the specific article with the parameters like I'm setting in the partial view.
Thanks.

I think your not using the ActionLink correctly. Change the ActionLink code to:
Html.ActionLink(
article.Title,
"ViewArticle",
"Article", // put the controller here
new
{
id = article.ArticleID,
path = article.Path
},
null)
Notice the null at then end.
EDIT: Why are you using [ChildActionOnly] in your controller? Since it is an MVC 2 feature I am assuming that you are using MVC2? Try removing it and check out the following article:
http://www.davidhayden.me/2009/11/htmlaction-and-htmlrenderaction-in-aspnet-mvc-2.html
I think the issue has to do with your partial not rendering. I would start by just trying to verify that your partial is rendering properly. Once you confirm that start to debug why the partial is not outputing.

I was able to solve the problem by using the following call in my RecentArticles action:
return PartialView("~/Views/Shared/Article/RecentArticles.ascx", viewData);
It seems like the partial view was not being rendered at all,
Thanks !

Related

How to create a module view and stick it onto a position in asp.NET MVC 4

Sory about my question, I am brand new to MVC 4 Razor, it's different from Asp.NET Web form.
Look like joomla, and other web languague, how can i create a "module", eg: "news, ads, counter" and stick it to asp.NET page.
I have a layout.cshtml in share folder, i think it's "Master Page" (like Master Page in Asp.NET webform)
How can i create some positions in that layout ?
You can create partial views or controller/actions that return a partial.
Partial Views
First create a partial view (which is a razor view without boilerplate markup like doctype, html and body elements.
To use a partial view in Razor:
#Html.Partial("name-of-partial-view", model-for-the-partial-view)
Actions returning a partial
To have a controller create a partial for you, create an action like this:
public DemoController : Controller
{
[ChildActionOnly] // Optional attribute, making this action invisible to the routing system
public ActionResult Demonstration(string someparam)
{
// Do something with someparam to get information to display
return PartialView();
}
}
You'll need to create a partial view to be returned from this action. (As before, a partial doesn't have the boilrplate markup like doctype, html and body.)
And to call it from Razor:
#Html.Action("Demonstration", "Demo", new { someparam = "something" });
If you want this partial on every page, put it somewhere in your layout page.

how to highlight selected tab of master page in asp.net mvc3

i have created a master page with lots of effort but i am not able to figure out how to make my tab selected based on the user click.
i have used one method to do that but finding very complicated as i have pass a viewdata from each of my controller which i dont like it, below is how i have done code in controller
ViewData["ActiveMenu"] = "Inbox";
and in my master page i have written a jquery like below to make the tab highlighted.
$('#lnkInbox').mouseout(function () {
$('#aInbox').removeClass('aInbox-Hover');
$('#aInbox').addClass('aInbox');
//put hover effect on the selected menu
var activeMenu = '<%:ViewData["ActiveMenu"] %>';
if (activeMenu == "Account") {
$('#aAccount').removeClass('aAccount');
$('#aAccount').addClass('aAccount-Hover');
}});
this is how i am doing but is there any other way i can do that...
please suggest
i have found one good link active menu item - asp.net mvc3 master page
but the answer which is showed there i am not able understand how to i utilize in my code and where to write the code in my project.
Use the answer you found.
To create helper class add new class to you project, i.e. like this
public static class LinkHelpers
{
//copy here the first block of code from the answer
}
Add to your HomeController methods (probably you already have them):
public class HomeController : Controller
{
public ActionResult About()
{
return View()
}
public ActionResult Index()
{
return View()
}
}
Create respective views and add to your master page
<ul>
<li>#Html.MenuLink("Main", "Index", "Home")</li>
<li>#Html.MenuLink("About us", "About", "Home")</li>
</ul>
And finally in your css file declare
.current{background-color:red;}

How can I run code from my layout file?

I used the following tutorial to help me build an RSS Reader in my ASP.NET MVC3 Razor application:
http://weblogs.asp.net/jalpeshpvadgama/archive/2011/08/17/creating-basic-rss-reader-in-asp-net-mvc-3.aspx
However, unlike the tutorial example, I want the RSS feed to be displayed on every page, and have therefore added it to my layout file, /Views/Shared/_Layout.cshtml
I currently only have 2 views on my site, and to get the RSS Reader to work on both views I've got the following code in my HomeController:
public class HomeController : Controller
{
//
// GET: /Index/
public ActionResult Index()
{
return View(CT.Models.RssReader.GetRssFeed());
}
public ActionResult About()
{
return View(CT.Models.RssReader.GetRssFeed());
}
}
From my WebForms experience, I would simply add the RSS Reader code in my master page code behind, and it would automatically work on every page.
Is there a Controller for layout pages which allows me to do the same?
How can I get this to work on every call of the layout page, without having to return anything?
EDIT: Following #Sebastian's advice, I've now added this code to a Partial View, removed CT.Models.RssReader.GetRssFeed() from return View() and included this in my layout file:
#Html.Partial("_MyPartialView")
The code in this partial view is:
<ul>
#foreach (var item in Model)
{
<li>
#item.Title
</li>
}
</ul>
However, I'm not getting a runtime error:
Object reference not set to an instance of an object.
It's erroring on the line #foreach (var item in Model)
You have to create a partial view and add functionality there.
Then in your layout, render this partial.
EDIT
Is your partial view really a partial view? The reason I said that is because you have "_" in front of the name which suggests that it might be a layout (might just be a naming convention).
To fix object reference error, you have to add the #Model declaration on top of your partial view.
Hope it helps.
UPDATE
In order to use different model in partial view, you need to explicitly declare which model you are going to use on render partialmethod.
#{Html.RenderPartial("../YourFeed", Model.YourFeedModel);}
Let me know if that resolved your issue.
The new error you are having is due to you not passing a Model to the partial view. You can do this with the second argument of the Html.Partial function...
Html.Partial("ViewName", MyModel);
As I think you are trying to do this in a Layout page you could also consider using a static reference to get your RSS feed. So forget about needing to pass in a Model and in your partial have:
#foreach (var item in RssRepository.GetFeed())
{
<li>
#item.Title
</li>
}
this like to a class something like...
public static RssRepository
{
public static MyModel GetFeed()
{
return new MyModel();//<- return what you would normally pass as a Model for RSS feeds
}
}
Hope that all makes sense

Create controller for partial view in ASP.NET MVC

How can I create an individual controller and model for a partial view? I want to be able to place this partial view any where on the site so it needs it's own controller. I am current rendering the partial as so
#Html.Partial("_Testimonials")
Why not use Html.RenderAction()?
Then you could put the following into any controller (even creating a new controller for it):
[ChildActionOnly]
public ActionResult MyActionThatGeneratesAPartial(string parameter1)
{
var model = repository.GetThingByParameter(parameter1);
var partialViewModel = new PartialViewModel(model);
return PartialView(partialViewModel);
}
Then you could create a new partial view and have your PartialViewModel be what it inherits from.
For Razor, the code block in the view would look like this:
#{ Html.RenderAction("Index", "Home"); }
For the WebFormsViewEngine, it would look like this:
<% Html.RenderAction("Index", "Home"); %>
It does not need its own controller. You can use
#Html.Partial("../ControllerName/_Testimonials.cshtml")
This allows you to render the partial from any page. Just make sure the relative path is correct.
If it were me, I would simply create a new Controller with a Single Action and then use RenderAction in place of Partial:
// Assuming the controller is named NewController
#{Html.RenderAction("ActionName",
"New",
new { routeValueOne = "SomeValue" });
}
The most important thing is, the action created must return partial view, see below.
public ActionResult _YourPartialViewSection()
{
return PartialView();
}
You don't need a controller and when using .Net 5 (MVC 6) you can render the partial view async
#await Html.PartialAsync("_LoginPartial")
or
#{await Html.RenderPartialAsync("PartialName");}
or if you are using .net core 2.1 > you can just use:
<partial name="Shared/_ProductPartial.cshtml"
for="Product" />
Html.Action is a poorly designed technology.
Because in your page Controller you can't receive the results of computation in your Partial Controller. Data flow is only Page Controller => Partial Controller.
To be closer to WebForm UserControl (*.ascx) you need to:
Create a page Model and a Partial Model
Place your Partial Model as a property in your page Model
In page's View use Html.EditorFor(m => m.MyPartialModel)
Create an appropriate Partial View
Create a class very similar to that Child Action Controller described here in answers many times. But it will be just a class (inherited from Object rather than from Controller). Let's name it as MyControllerPartial. MyControllerPartial will know only about Partial Model.
Use your MyControllerPartial in your page controller. Pass model.MyPartialModel to MyControllerPartial
Take care about proper prefix in your MyControllerPartial. Fox example: ModelState.AddError("MyPartialModel." + "SomeFieldName", "Error")
In MyControllerPartial you can make validation and implement other logics related to this Partial Model
In this situation you can use it like:
public class MyController : Controller
{
....
public MyController()
{
MyChildController = new MyControllerPartial(this.ViewData);
}
[HttpPost]
public ActionResult Index(MyPageViewModel model)
{
...
int childResult = MyChildController.ProcessSomething(model.MyPartialModel);
...
}
}
P.S.
In step 3 you can use Html.Partial("PartialViewName", Model.MyPartialModel, <clone_ViewData_with_prefix_MyPartialModel>). For more details see ASP.NET MVC partial views: input name prefixes

ASP.NET MVC2: modifying master css property depending on query string parameter

I am migrating a web site to a new one using ASP .NET MVC2.
In the original site, master page has code-behind to check a query string parameter value. Depending on this value, code-behind dynamically modify some CSS property to hide / display master page elements.
As MVC2 has no code-behind because we are supposed to perform everything in the controllers, how should I proceed in this case ?
I see this : asp.net mvc modifying master file from a view
It partially answers my needs but the query string processing is common to all pages. How can I move this processing in a common code section ?
Regards.
A helper method looks like a good place:
public static class HtmlHelperExtensions
{
public static string GetCss(this HtmlHelper htmlHelper)
{
// read some request parameter
// here you also have access to route data so the
// parameter could be part of your custom routes as well
var foo = htmlHelper.ViewContext.HttpContext.Request["foo"];
// based on the value of this parameter
// return the appropriate CSS class
return (foo == "bar") ? "barClass" : "fooClass";
}
}
And somewhere in your master page:
<body class="<%= Html.GetCss() %>">
Or if you are always going to apply it to the body tag only it might be more appropriate to do this in order to reduce the tag soup:
public static class HtmlHelperExtensions
{
public static MvcHtmlString StartBody(this HtmlHelper htmlHelper)
{
var body = new TagBuilder("body");
var foo = htmlHelper.ViewContext.HttpContext.Request["foo"];
var bodyClass = (foo == "bar") ? "barClass" : "fooClass";
body.AddCssClass(bodyClass);
return MvcHtmlString.Create(body.ToString(TagRenderMode.StartTag));
}
}
and in your master page at the place of the body tag:
<%= Html.StartBody() %>
I can think of two solutions to this:
Derive your controllers from one controller base and set the ViewData parameter there depending on posted Form values
Don't use ViewData at all, but simply look for the form value in the view (using HttpContext.Current)
The second method violates the MVC pattern. IMO it is still acceptable in some scenarios, for example I am using this approach to highlight the currently selected item in a navigation menu.

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