In rails, page templates have their own controller which is called before a page is rendered (I think?).
Likewise, can I have a controller associated with a partial that is called before the partial is rendered?
I know you can pass local variable into a partial, but I want to run a good few lines of code to assign those local variables, which if I wasn't using a partial I would have put in the controller.
This code that you want to run should be in a helper that can be called from the controller, or from the partial itself.
Related
I am very new in asp.net MVC kindly let me know where is should use partial view and where i should Render Partial view . Thanks in advance
This link might help.
Html.RenderPartial
This method result will be directly written to the HTTP response stream means it used the same TextWriter object as used in the current webpage/template.
This method returns void.
Simple to use and no need to create any action.
RenderPartial method is useful when the displaying data in the partial view is already in the corresponding view model.
For example : In a blog to show comments of an article, we would like to use RenderPartial method since an article information with comments are already populated in the view model.
#{Html.RenderPartial("_Comments");}
This method is faster than Partial method since its result is directly written to the response stream which makes it fast.
Html.Partial
Renders the partial view as an HTML-encoded string.
This method result can be stored in a variable, since it returns string type value.
Simple to use and no need to create any action.
Like RenderPartial method, Partial method is also useful when the displaying data in the partial view is already in the corresponding view model.
For example: In a blog to show comments of an article, you can use Partial method since an article information with comments are already populated in the view model.
#Html.Partial("_Comments")
Both of these helper method are used for rendering partial views
Both have different syntax in razor view #Html.Partial("_student", items) and {Html.RenderPartial("_student", items);}, since render partial return void and the output is written directly to output stream, it has different syntax than Partial.
Syntax in web from view
<%:Html.Partial("_student") %> and <% Html.RenderPartial("_student"); %>
Partial Returns MVCHtmlString, which can be assigned to variables.
Performance wise Render partial is better as it writes directly to output stream.
And of-course you can find a lot of references online and within stack overflow to read
I was trying to create an action for one of the partials in my rails application, but wondered how to name it. Does it have the underscore at the beginning? Like:
def _my_partial
end
or no underscore? Not mentioned in the controllers guide
A partial is a piece of view which is embedded in the main view or within another partial. The purpose of a partial is typically for re-use or to making view code cleaner.
If you need to use an action to render a partial, then it's probably better to either:
make your partial into a view, or
create a view to embed your partial.
See Rails 4 - passing variable to partial
I've seen how to use Partial Views from within a View and I understand how a model is passed from the View to a Partial View. What I don't grasp is how to include a Partial View inside of _Layout.cshtml so that I can pass it to the Partial View - or, how the Partial View itself can call a Controller Action to create a Model for use.
Specifically, I want to include a Partial View within _Layout.cshtml to display in the header of every page. The Partial View will display a custom setting in the User Profile. I can't think of any way to obtain the Model without making a Controller Action call - but how is this done in/for a Partial View from within _Layout.cshtml?
Is my only option of accessing a Controller Action to build my Partial View's required Model to use a jQuery call? Or is there another way?
The answer is by calling #Html.Action().
It sounds like you're on the right track.
The key is to try to not pass multiple models around, make models complicated, or use the ViewBag needlessly.
Instead, any time you want information on every page, call an action from your _Layout.
For example, you might have a controller called PartialsController or SharedController.
public class PartialsController : Controller
{
[ChildActionOnly]
public ActionResult UserProfilePartial()
{
UserProfileModel model = new UserProfileModel();
return PartialView("_UserProfile", model);
}
}
The ChildActionOnlyAttribute means that users cannot access the action directly. Only your code can call the action. You can also apply the attribute to the controller so that it affects all actions automatically.
Now call the action from your view (_Layout).
#Html.Action("UserProfilePartial", "Partials")
I have several shared razor partial views in my application to show some details of products on different pages. Now i need to change some of links inside partial views depending on what main view rendered that partial.
For example:
If partial view is rendered inside "index.cshtml", one of the links in partial view should be:
site1 called from index.cshtml
and if it's inside "insert.cshtml" then link need to be
other site that's not 1 and it's called from insert.cshtml
something like:
#if (something.parentview = "index.cshtml")
{ site1 called from index.cshtml}
else {
other site that's not 1 and it's called from insert.cshtml
}
Is there a way to do this?
When you call the Shared PartialView you know where are you.
Is far more easy to pass a parameter to your partial at the time of rendering that rely in "detect" inside of which view is rendered. Imagine... you have 3 levels of nesting... things get more complicated. Imagine if you change routing or view names?
You can use the ViewBag to pass the parameter: in your view you can set something to check inside the Partial. Not controller code is needed.
A more robust approach is pass a ViewModel to your Partial, but if the only data you need to pass is just a parameter, the ViewBag is simpler.
I have a partial view in my Foo folder. I want to show it on my Home/index view. I am using partial render and it is trying to locate it in temp folder. How to write Renderpartial to render foo\partial view ?
regards,
Asif hameed
To get it to render just specify the path in RenderPartial like this:
<%Html.RenderPartial("~/Areas/FooArea/Views/Foo.ascx");%>
Obviously replace my example path with the path to your actual Foo partial view.
If you want to call an action that returns a partial view on another controller (foo) try using Html.RenderAction. It will allow you to pass in an action and a controller.
This post has a decent description of the differences between RenderPartial/RenderAction and when to use each one: http://www.arrangeactassert.com/when-to-use-html-renderpartial-and-html-renderaction-in-asp-net-mvc-razor-views/