I am a beginner and I am going through some tutorials in my MVC. So, I came across two scenarios.
Scenario 1.
I had to pass some data to my view on post and then send that data as hidden field. Here is the code.
[HttpPost]
[ValidateAntiForgeryToken]
public ActionResult ForgotPassword(ForgotPasswordMV viewModel)
{
if (ModelState.IsValid)
{
return RedirectToAction("VerifyToken", new { emailId = viewModel.EmailId });
}
^^ USING ANONYMOUS OBJECTS
return View();
}
public ActionResult VerifyToken(string emailId = null)
{
VerifyTokenMV viewModel = new VerifyTokenMV
{
EmailId = emailId
};
return View(viewModel);
}
VerifyToken View
#using (#Html.BeginForm("VerifyToken", "Security"))
{
#Html.HiddenFor(m => m.EmailId)
<button class="btn btn-primary">Continue</button>
}
Works Perfectly fine. I am able to receive values of EmailId. So far so good.
Scenario 2.
Needed to open a partial view from Main view, here is the snippet.
Main cshtml file
<div class="abc">
#Html.Partial("../Widget/Customize", Model.Unit, new ViewDataDictionary() { { "ElementName", "UnitWidget" } })
</div>
partial cshtml file
#{
string custWidgetElementName = ViewBag.ElementName;
}
// some html code below
Observation:
In scenario 2 why have I used ViewDataDictionary. Although both example works perfectly fine. But is there any reason that I had to use ViewDataDictionary. In scenraio 1 can we use ViewDataDictionary? If Yes, then which one is optimum solution.
Question: When I need to pass values shall I use new {key : value} or use ViewDataDictionary or there is no corelation? Instead of ViewDataDictionary can I use anonymous object in Senario 2
Your two scenarios are totally different. They are not doing the same thing.
In scenario 1 when using this line:
return RedirectToAction("VerifyToken", new { emailId = viewModel.EmailId });
A new URL is genrated and sent back to the client (the browser) with HTTP Code 301 or 302. When received the browser will re-contact your application wiht the received URL. With that URL, your application will execute the associated action. In your case, the client's browser will call VerifyToken action with the emailId parameter setted when you call RedirectionToAction into ForgotPassword action. So using RedirectionToAction method is just telling that method to generate a new URL with parameter defined in the anonymous type.
In scenario 2 is completely different to scenario 1. With this line:
#Html.Partial("../Widget/Customize", Model.Unit, new ViewDataDictionary() { { "ElementName", "UnitWidget" } })
You're telling your view to inject the partial view which path is ../Widget/Customize. Because that partial view the strongly typed, you passed Model.Unit as an second parameter. You use also a third parameter new ViewDataDictionary() { { "ElementName", "UnitWidget" } } because your partial seems to internally need to access to the dynamic property ViewBag or dictionary property ViewData of your view.
Conclusion:
In scenario 1 you are just telling the client's browser to go to the new URL you have generated after requesting ForgetPassword URL. We just call that a rediretion.
In scenario 2, you're just rendering a partial view into a view. The client's broswer doesn't know anything what's going on with partial views they don't know if they exist.
Related
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.
I'm using ASP.NET MVC 4. I am trying to pass data from one controller to another controller. I'm not getting this right. I'm not sure if this is possible?
Here is my source action method where I want to pass the data from:
public class ServerController : Controller
{
[HttpPost]
public ActionResult ApplicationPoolsUpdate(ServiceViewModel viewModel)
{
XDocument updatedResultsDocument = myService.UpdateApplicationPools();
// Redirect to ApplicationPool controller and pass
// updatedResultsDocument to be used in UpdateConfirmation action method
}
}
I need to pass it to this action method in this controller:
public class ApplicationPoolController : Controller
{
public ActionResult UpdateConfirmation(XDocument xDocument)
{
// Will add implementation code
return View();
}
}
I have tried the following in the ApplicationPoolsUpdate action method but it doesn't work:
return RedirectToAction("UpdateConfirmation", "ApplicationPool", new { xDocument = updatedResultsDocument });
return RedirectToAction("UpdateConfirmation", new { controller = "ApplicationPool", xDocument = updatedResultsDocument });
How would I achieve this?
HTTP and redirects
Let's first recap how ASP.NET MVC works:
When an HTTP request comes in, it is matched against a set of routes. If a route matches the request, the controller action corresponding to the route will be invoked.
Before invoking the action method, ASP.NET MVC performs model binding. Model binding is the process of mapping the content of the HTTP request, which is basically just text, to the strongly typed arguments of your action method
Let's also remind ourselves what a redirect is:
An HTTP redirect is a response that the webserver can send to the client, telling the client to look for the requested content under a different URL. The new URL is contained in a Location header that the webserver returns to the client. In ASP.NET MVC, you do an HTTP redirect by returning a RedirectResult from an action.
Passing data
If you were just passing simple values like strings and/or integers, you could pass them as query parameters in the URL in the Location header. This is what would happen if you used something like
return RedirectToAction("ActionName", "Controller", new { arg = updatedResultsDocument });
as others have suggested
The reason that this will not work is that the XDocument is a potentially very complex object. There is no straightforward way for the ASP.NET MVC framework to serialize the document into something that will fit in a URL and then model bind from the URL value back to your XDocument action parameter.
In general, passing the document to the client in order for the client to pass it back to the server on the next request, is a very brittle procedure: it would require all sorts of serialisation and deserialisation and all sorts of things could go wrong. If the document is large, it might also be a substantial waste of bandwidth and might severely impact the performance of your application.
Instead, what you want to do is keep the document around on the server and pass an identifier back to the client. The client then passes the identifier along with the next request and the server retrieves the document using this identifier.
Storing data for retrieval on the next request
So, the question now becomes, where does the server store the document in the meantime? Well, that is for you to decide and the best choice will depend upon your particular scenario. If this document needs to be available in the long run, you may want to store it on disk or in a database. If it contains only transient information, keeping it in the webserver's memory, in the ASP.NET cache or the Session (or TempData, which is more or less the same as the Session in the end) may be the right solution. Either way, you store the document under a key that will allow you to retrieve the document later:
int documentId = _myDocumentRepository.Save(updatedResultsDocument);
and then you return that key to the client:
return RedirectToAction("UpdateConfirmation", "ApplicationPoolController ", new { id = documentId });
When you want to retrieve the document, you simply fetch it based on the key:
public ActionResult UpdateConfirmation(int id)
{
XDocument doc = _myDocumentRepository.GetById(id);
ConfirmationModel model = new ConfirmationModel(doc);
return View(model);
}
Have you tried using ASP.NET MVC TempData ?
ASP.NET MVC TempData dictionary is used to share data between controller actions. The value of TempData persists until it is read or until the current user’s session times out. Persisting data in TempData is useful in scenarios such as redirection, when values are needed beyond a single request.
The code would be something like this:
[HttpPost]
public ActionResult ApplicationPoolsUpdate(ServiceViewModel viewModel)
{
XDocument updatedResultsDocument = myService.UpdateApplicationPools();
TempData["doc"] = updatedResultsDocument;
return RedirectToAction("UpdateConfirmation");
}
And in the ApplicationPoolController:
public ActionResult UpdateConfirmation()
{
if (TempData["doc"] != null)
{
XDocument updatedResultsDocument = (XDocument) TempData["doc"];
...
return View();
}
}
Personally I don't like to use TempData, but I prefer to pass a strongly typed object as explained in Passing Information Between Controllers in ASP.Net-MVC.
You should always find a way to make it explicit and expected.
I prefer to use this instead of TempData
public class Home1Controller : Controller
{
[HttpPost]
public ActionResult CheckBox(string date)
{
return RedirectToAction("ActionName", "Home2", new { Date =date });
}
}
and another controller Action is
public class Home2Controller : Controller
{
[HttpPost]
Public ActionResult ActionName(string Date)
{
// do whatever with Date
return View();
}
}
it is too late but i hope to be helpful for any one in the future
If you need to pass data from one controller to another you must pass data by route values.Because both are different request.if you send data from one page to another then you have to user query string(same as route values).
But you can do one trick :
In your calling action call the called action as a simple method :
public class ServerController : Controller
{
[HttpPost]
public ActionResult ApplicationPoolsUpdate(ServiceViewModel viewModel)
{
XDocument updatedResultsDocument = myService.UpdateApplicationPools();
ApplicationPoolController pool=new ApplicationPoolController(); //make an object of ApplicationPoolController class.
return pool.UpdateConfirmation(updatedResultsDocument); // call the ActionMethod you want as a simple method and pass the model as an argument.
// Redirect to ApplicationPool controller and pass
// updatedResultsDocument to be used in UpdateConfirmation action method
}
}
I have an MVC 4 app and I am using a RESTful methodology for my URLs. I have the following routes registered in my app (along with others that are not relevant to my question:
//EDIT
routes.MapRoute(alias + "_EDIT", alias + "/{id}/edit",
new { controller = controllerName, action = "edit" },
new { httpMethod = new RestfulHttpMethodConstraint(HttpVerbs.Get) });
//PUT (update)
routes.MapRoute(alias + "_PUT", alias + "/{id}",
new { controller = controllerName, action = "update" },
new { httpMethod = new RestfulHttpMethodConstraint(HttpVerbs.Put) });
I have the following methos in my controller mapping to these routes:
public override ActionResult Edit(int id)
{...}
public override ActionResult Update(RequestEditViewModel userModel)
{
if (!ModelState.IsValid)
{
//do some stuff to ensure lookups are populated
...
return View("Edit", userModel);
}
}
In my app when I perform a request to edit a request my URL looks like:
http://server/request/1/edit
it correctly calls the Edit method on my controller.
My Edit.cshtml uses the followng to ensure the Update method is called on PUT:
#using (Html.BeginForm("Update", "Request"))
{
#Html.HttpMethodOverride(HttpVerbs.Put);
...
}
My form is generated as follows:
<form action="/requests/71" method="post" autocomplete="off" novalidate="novalidate">
<input name="X-HTTP-Method-Override" type="hidden" value="PUT"/>
...
</form>
When I click the submit button it correctly calls my Update method.
OK...Now for the issue. If my model is NOT valid I want to return back the Edit model. As you can see in the above code but, the URL is the one called from the submit button:
http://server/request/1
not
http://server/requests/1/edit
I have tried an reviewed two other options but both of these redirect the request back through the Edit method again which adds additional overhead and also puts all the model values in the querystring which I do NOT want:
return RedirectToAction("Edit", userModel);
return RedirectToRoute("requests_Edit", userModel);
So, is there a way to just return the View as I have in my code but, ensure the URL changes back and include the "/edit"?
The only alternative I have come up with is to perform an AJAX call and put the update that way the URL never changes, but I was trying to avoid that for this form.
Conceptually, you want to be doing something like a Server.Transfer (that is, making on URL appear to be another.) This discussion may be of use to you:
How to simulate Server.Transfer in ASP.NET MVC?
I have a model that I am using in my view that is full of data. This data is then edited in the view. I need to figure out a way to resubmit this data back over to the controller.
Here is what I have so far.
VIEW:
#using (Html.BeginForm("DownloadCSV", "Respondents", FormMethod.Post))
{
#Html.HiddenFor(m => m.FilterSet)
<div class="btn btn-default pull-right" id="dispoCSV" onclick="$('#csvFormSubmit').click()">
<i class="icon-file-alt"></i> Disposition Report
</div>
<input id="csvFormSubmit" type="submit" style="display:none;" />
}
CONTROLLER:
[HttpPost]
public ActionResult DownloadCSV(RespondentsFilterSet model)
{
string csv = "Charlie, Test";
return File(new System.Text.UTF8Encoding().GetBytes(csv), "text/csv", "DispositionReport.csv");
}
MODEL:
public class RespondentsFilterSet : ColdListFilterSet
{
public List<int> OwningRecruiters { get; set; }
public List<int> RecruitingGroups { get; set; }
public override bool HasAtLeastOneFilter()
{
return base.HasAtLeastOneFilter() || OwningRecruiters.IsNotNullOrEmpty() || RecruitingGroups.IsNotNullOrEmpty();
}
public override ExpressionBase ToExpression()
{
var expr = base.ToExpression();
var expressions = expr == null ? new List<ExpressionBase>() : new List<ExpressionBase> { expr };
if (OwningRecruiters.IsNotNullOrEmpty())
{
expressions.Add(new InExpression<int> { Field = Create.Name<Respondent>(r => r.RecruitedBy), Values = OwningRecruiters });
}
if (RecruitingGroups.IsNotNullOrEmpty())
{
expressions.Add(new InExpression<int> { Field = Create.Name<Respondent>(r => r.RecruitingGroupId), Values = RecruitingGroups });
}
return expressions.Count == 0 ? null : BuildAndExpressionFromList(expressions);
}
}
I realize that my controller is not not finalized. I just have displaying some static csv. But I can't figure out why my model from my view is always null when returned to the controller.
Just look at your form. There's not a single input element (except the submit button). You cannot expect to get anything back on the server in this case.
Please read about HTML and how forms work in HTML. In HTML forms you have input fields. Things like text fields, hidden fields, checkboxes, radio buttons, ... - fields that the user interacts with get submitted to the server.
The fact that you have made your HttpPost controller action take some model as parameter doesn't mean at all that this parameter will be initialized. In ASP.NET MVC you have a default model binder. This model binder looks at what gets sent to the server as values when the form is submitted and uses the names of the fields to bind to the corresponding properties. Without input fields in the form, nothing gets sent to the server. Just use the debugging tools built into your web browser to inspect what exactly gets sent to the server.
Contrary to classic ASP.NET WebForms, ASP.NET MVC is stateless. There's no ViewState to remember your model.
So all this rambling is to say that you should read more about HTML forms first and understand the stateless nature of the web before getting into ASP.NET MVC. As far as your particular problem is concerned, well, assuming the user is not supposed to modify any values of the view model in your view throughout some input fields, you could simply include a hidden field containing the id of your model in the form. This id will then be sent to your POST controller action as parameter and you could use it to retrieve your original model from wherever it is stored (I guess a database or something).
I have a view that displays a list of comments. It does this via the DisplayTemplate. All I have to do is something like #Html.DisplayFor(x => x.BlogPost.PostComments) and all the comments render appropriately.
There is a form at the bottom of the page to add a new comment. This page utilizes progressive enhancement. So if javascript is disabled then the form submits like normal, adds the comment to the database, then redirects to the action that renders the blog post. However, if javascript is available then jQuery hijacks the form's submit and makes the post via ajax. Well because the comment markup is in a display template, I don't know how to return it from the action method so that jQuery can drop it on the page.
I know how to do this with partial views. I would just have the action method return the right partial view and jquery would append the response to the comment container on the page.
Before I go chopping out my display template in favor of a partial view, is there a straight forward way that I'm missing to send back a display template from the controller?
Here is my action method:
public ActionResult AddComment(PostComment postComment)
{
postComment.PostedDate = DateTime.Now;
postCommentRepo.AddPostComment(postComment);
postCommentRepo.SaveChanges();
if (Request.IsAjaxRequest())
return ???????
else
return RedirectToAction("BlogPost", new { Id = postComment.BlogPostID });
}
When the page loads it doesn't need to worry about it because it uses the templates in the standard way:
<div class="comments">
#Html.DisplayFor(x => x.BlogPost.BlogPostComments)
</div>
I just want to know how I might send a single comment that utilizes the display template back to jQuery.
You may try returning the partial HTML representing the newly posted comment:
if (Request.IsAjaxRequest())
{
return PartialView(
"~/Views/Shared/DisplayTemplates/Comment.cshtml",
postComment
);
}
and on the client side append this comment to the comments container:
$.post('#Url.Action("AddComment")', { ... }, function (result) {
$('#comments').append(result);
// or $('#comments').prepend(result); if you want it to appear on top
});
Does this question give you what you are looking for? Seems to indicate that you can call a HTML helper from an action.
Create a partial view /Shared/DisplayTemplate.cshtml with the following razor code:
#Html.DisplayFor(m => Model)
Then in your controller (or preferably in a base controller class) add a method along these lines:
protected PartialViewResult PartialViewFor(object model)
{
return PartialView("DisplayTemplate",model);
}
In the OP's case then:
public ActionResult AddComment(PostComment postComment)
{
postComment.PostedDate = DateTime.Now;
postCommentRepo.AddPostComment(postComment);
postCommentRepo.SaveChanges();
if (Request.IsAjaxRequest())
return PartialViewFor(postComment);
else
return RedirectToAction("BlogPost", new { Id = postComment.BlogPostID });
}