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Execute a controller from view in ASP.NET MVC - Razor

I am trying to print the name of the user who executes my web app. It is written in MVC-Razor.
From the initial View, I would to execute the controller below:
[Authorize]
public ActionResult Check()
{
var check = new CheckAD();
var user = new User {Name = check.CheckSecurityWithAD()};
if (!string.IsNullOrEmpty(user.Name))
{
return View("Checked", user);
}
var errors = new ErrorsModel()
{
Messages = new List<string>(){"You don't have permission"}
};
return View("Error", errors);
}
This controller returns another view if the user is correctly authenticated:
#model UsersActivationWeb.Models.User
#{
ViewBag.Title = "Checked";
}
#{ <p> Logged come #Model.Name </p>};
How can I print the second view (I think it's a partial view) in the first one using the controller?
Thanks

Sounds to me like you need an Html.Action. This will run the controller code and display the view contents that are produced where you place the call.
Most likely you will need this overload, Html.Action(string actionName, string controllerName).
Assuming the controller is called CheckController. In your initial view call it like this
#Html.Action("Check","Check")
Since you don't want people navigating to the Check view you should give it a ChildActionOnly attribute so it looks like this
[Authorize]
[ChildActionOnly]
public ActionResult Check()
{
//rest of code
}
Finally you almost certainly don't want the layout contents to appear with the Checked view so change your Checked view to this
#model UsersActivationWeb.Models.User
#{
Layout = null;
}
#{ <p> Logged come #Model.Name </p>};
Since you are doing authorization logic in the Check action you might not need the Authorize attribute. I say that because with it a user not logged in will not get the error or their name. Maybe you want this though, I'd need to know more about your code to say for sure.
This way you will either get the name of the user or the errors as required.

Send Selected DropDownList value to HomeController ActionResult

Hi I have a drop down list that is filled in from comma delimited values in the config. This works fine.
What I am trying to do is to send the selected value on button click to a ActionResult in the HomeController.
I created a Model, which is taking a string. When I hit the button I get error:
The view 'TestAction' or its master was not found or no view engine supports the searched locations.
This is what my Controller looks like:
[HttpPost]
[ActionName("TestAction")]
public ActionResult TestAction(SQL_Blocks_App.Models.DropdownList SelectedValue)
{
//System.Diagnostics.Debug.WriteLine(SelectedValue);
return View();
}
This is what my model looks like:
public class DropdownList
{
//
// GET: /DropdownList/
[Display(Name = "Servers")]
public string SelectedValue{ get; set; }
}
and this is what my Index View looks like:
<form id="SelectedValue" action="/Home/TestAction" method="post" style="margin: 0">
<div class="col-lg-5">
#{
ViewBag.Title = "Index";
}
#Html.DropDownList("YourElementName", (IEnumerable<SelectListItem>)ViewBag.DropdownVals, "--Choose Your Value--", new
{
//size = "5",
style = "width: 600px"
})
</div>
<div class="col-lg-5">
<input type="submit" value="Run Query" />
<input id="Button2" type="button" value="Clear" onclick="window.location.reload()" />
</div>
</form>
I want to clarify. My end goal is to use the selected value in a SQL query in the ActionResult and return the results back to the index so I can fill them in a table. ( You don't have to show me how to do the SQL part for now I just would like to see the selected value at least printed in the output.)

Redirect to index action, and pass the parameters along
[HttpPost]
[ActionName("TestAction")]
public ActionResult TestAction(SQL_Blocks_App.Models.DropdownList _selectedValue)
{
//System.Diagnostics.Debug.WriteLine(SelectedValue);
return RedirectToAction("Index", "[Controller]", new {#_selectedValue = _selectedValue });
}
and then your Index method should accept the parameter.
[HttpGet]
public ActionResult Index(SQL_Blocks_App.Models.DropdownList _selectedValue)
{
//use _selectedValue
}
I would recommend using another method other than your index, or make Dropdownlist nullable/set a default for it.

The default framework behavior of return View() is to return a view with the same name as the currently-executing action. Which is TestAction. The error is telling you that no such view was found.
You have a couple of options. You can either create the view, or you can return something else. For example, if you want to redirect back to the Index then you can return a redirect result:
return RedirectToAction("Index");
You could also specify the Index view in the response:
return View("Index");
However, keep in mind that the URL will still be for TestAction and not for Index, which could result in unexpected changes to behavior if you're not aware of this.
Edit: Based on comments on this answer, it sounds like what you actually want is to build a pair of actions which generally operate on the same view. This isn't particularly common for an index view, but is very common for edit views. The only difference is semantics, structurally the concept works anywhere.
Consider two actions:
public ActionResult Index()
{
// just show the page
return View();
}
[HttpPost]
public ActionResult Index(SQL_Blocks_App.Models.DropdownList SelectedValue)
{
// receive data from the page
// perform some operation
// and show the page again
return View();
}
Requests between these two actions would differ only by the HTTP verb (GET or POST), not by the action name on the URL. That name would always be "Index". But when the form on the index view is submitted via POST and has a "SelectedValue", the second action is invoked instead of the first.
In that second action you would perform your database interaction, gather whatever data you needed, and if necessary include a model or some additional data in the response.

You TestAction method is returning to a View. Make sure View TestAction.cshtml exists and is in the Home folder.

Generate view without controller action

In my ASP.NET MVC project I have a controller that one action just result view. This Action does not get any argument and just return a CSHTML page. This page could not be partial.
Does anybody know a better way to generate view - I mean can I generate view without controller action?
//Edit - sample codes
Right now in my UserPanelController i have an action ChangeSettings
[HttpGet]
public ActionResult ChangeSettings()
{
return View("Configuration");
}
So if i want to get a configuration View i have to do request to controller from for example navigation:
<nav>
<div class="nav-wrapper">
Logo
<ul id="nav-mobile" class="right hide-on-med-and-down">
<li>Sass</li>
<li>Components</li>
<li>Konrad</li>
</ul>
</div>
</nav>
Can i get a ConfigurationView without my controller action?

Maybe I'm a bit too late but what you are probably looking for is this:
#{ Html.RenderPartial("_PartialViewName"); }
Notice that you can use a model in your view as well, by passing it directly from the view that is calling the partial one.

You can render a view yourself by calling the following method
private static string RenderPartialViewToString(Controller controller, string viewName, object model)
{
controller.ViewData.Model = model;
using (var sw = new StringWriter())
{
var viewResult = ViewEngines.Engines.FindPartialView(controller.ControllerContext, viewName);
var viewContext = new ViewContext(controller.ControllerContext, viewResult.View, controller.ViewData, controller.TempData, sw);
viewResult.View.Render(viewContext, sw);
return sw.ToString();
}
}
This will give you html string containing your rendered view. I've used this before to render HTML for emails where the email content changed from user to user.
Hope this helps.

If it is static content, you can add an .html file inside your project. The web server will serve it.
To make sure the MVC routing will not interfer you can add something like this to your routes:
routes.IgnoreRoute("{file}.html");

MVC Maintaining Model through multi view form submits

So I am working on a MVC which is basically three steps.
Create a view for each step i.e.
StepOne
StepTwo
StepThree
On step one and two I ask the users to enter some details.
All the values for the multiple step I store in one Model.
And getting from StepOne to StepTwo is fine. Certain values in my model are being set and maintained.
But on StepTwo when I do my second httppost and pass the model, it seems to just create a new instance of the model and values from stepone are not maintained.
<% using (Html.BeginForm("StepTwo", "Home", FormMethod.Post, new { id = "restrictionForm" })) { %>
<%: Html.AntiForgeryToken() %>
<div id="wrapping" class="clearfix">
<h3>Postcode Restriction Type : </h3>
<%= Html.DropDownListFor(x => x.SelectedRestriction, Model.RestrictionTypes,"Select Restriction...", new { #class = "selmenu required" }) %>
<h3>Restriction Description : </h3>
<%= Html.TextBoxFor(m => m.RestrictionDescription, new { #class = "txtblock required" }) %>
</div>
<section id="buttons">
<input type="submit" value="Submit" id="submitBtn" />
</section>
And in my controller
On Page Load my Model is still intact and still maintains values from previous step.
[Authorize]
public ActionResult StepTwo(PostcodesModel model)
{
var summaryMessage = "";
model.SummaryMessage = summaryMessage;
model.RestrictionTypes = _Provider.GetRestrictionTypes();
return View(model);
}
But at the Httppost, the model has lost values and seems to have created new instance of model.
[Authorize]
[HttpPost]
[ActionName("StepTwo")]
[ValidateAntiForgeryToken]
public ActionResult StepTwoPost(PostcodesModel model)
{
return View(model);
}
Any idea how I can maintain model between Http Posts ?

It seems from your question that you believe models persist across requests. This is not true.
You either pass information to the view via your model from the controller, or submit values from your view to your controller and MVC handles this by binding html form inputs to your View Model.
If you want to persist your View Model across each step you need to take the values accepted and copy them into a new model (or directly inject it) when calling your new view.
Something like this (I just typed this up off my head so its not clean but should give you an idea):
[HttpGet]
public ActionResult StepOne()
{
var model = new MyNewModel();
return View(model);
}
/* NOTE THE MODEL PASSED BACK HERE IS NOT THE EXACT SAME OBJECT
AS THE ONE CREATED IN THE GET ACTION ABOVE, MODEL BINDING HAS OCCURRED
TO READ YOUR FORM INPUTS AND MATCH THEM TO A NEW MODEL WHICH IS EXPECTED */
[HttpPost]
public ActionResult StepOne(MyNewModel model)
{
if (ModelState.IsValid)
{
// Do something here
// pass model to new view
TempData["model"] = model;
return RedirectToAction("StepTwo");
}
return View(model);
}
[HttpGet]
public ActionResult StepTwo()
{
MyNewModel model;
if (TempData["model"] != null)
{
model = (MyNewModel) TempData["model"];
// make some changes if necessary
model.MyProperty = 2;
return View(model);
}
return RedirectToAction("StepOne");
}

I think you can also keep your model in Session ( per application ) or in a ViewState ( per page ).
Every time you make a post you upgrade the session. It's also optimal because on the client side you receive only a session identifier.
Some differences between Session and Viewstate:
Session is per application, while ViewState is per page
Session sends to the client side only a session identifier, while ViewState sends an ecrypted text

Why isn't viewbag value passing back to the view?

straight forward question , can't seem to get my viewBag value to display in a view that the user is directed to after completing a form.
Please advise..thanks
My Index ActionResult simple returns model data..
public ActionResult Index()
{
var source = _repository.GetByUserID(_applicationUser.ID);
var model = new RefModel
{
test1 = source.test1,
};
return View(model);
}
My Get Edit" ActionResult , simply uses the same model data as Index.
My Post "Edit" ActionResult, assigns the new values if any to the model and redirects to the Index page, but Index page does not display ViewBag value ??
[HttpPost]
public ActionResult Edit(RefModell model)
{
if (ModelState.IsValid)
{
var source = _repository.GetByUserID(_applicationUser.ID);
if (source == null) return View(model);
source.test1 = model.test1;
_uow.SaveChanges();
#ViewBag.Message = "Profile Updated Successfully";
return RedirectToAction("Index");
}
return View(model);
}
And in my Index view...
#if(#ViewBag.Message != null)
{
<div>
<button type="button">#ViewBag.Message</button>
</div>
}

ViewBag only lives for the current request. In your case you are redirecting, so everything you might have stored in the ViewBag will die along wit the current request. Use ViewBag, only if you render a view, not if you intend to redirect.
Use TempData instead:
TempData["Message"] = "Profile Updated Successfully";
return RedirectToAction("Index");
and then in your view:
#if (TempData["Message"] != null)
{
<div>
<button type="button">#TempData["Message"]</button>
</div>
}
Behind the scenes, TempData will use Session but it will automatically evict the record once you read from it. So it's basically used for short-living, one-redirect persistence storage.
Alternatively you could pass it as query string parameter if you don't want to rely on sessions (which is probably what I would do).

RedirectToAction causes an HTTP 302 response, which makes the client make another call to the server and request a new page.
You should be returning a view instead of redirecting.

The RedirectToAction(msdn) instructs your browser to make a new request.
So your server will be called again but it will be a new request with a blank viewbag and all
You could do a sort of internal redirect by just calling the index method, this way the viewbag will still have its data.
Edit : you'll also have to modify your index method or your View(model) line will try to render the edit. Full code below
public ActionResult Index()
{
var source = _repository.GetByUserID(_applicationUser.ID);
var model = new RefModel
{
test1 = source.test1,
};
return View("Index",model);
}
[HttpPost]
public ActionResult Edit(RefModell model)
{
if (ModelState.IsValid)
{
var source = _repository.GetByUserID(_applicationUser.ID);
if (source == null) return View(model);
source.test1 = model.test1;
_uow.SaveChanges();
#ViewBag.Message = "Profile Updated Successfully";
return Index();
}
return View(model);
}

You can try this way also
Controller
public ActionResult Test()
{
ViewBag.controllerValue= "testvalue";
..................
}
View -
define top of razor page
#{string testvalue= (string)ViewBag.controllerValue;}
$(function () {
var val= '#testvalue';
});