Is there a simple way to pass data into an MVC3 app? - asp.net-mvc-3

[Edit] To try to clarify:
I have a view that needs to be launched from an external application. The application requires string data to be passed from an external application (the data is free text and too long to pass as a query parameter), So I would like to launch the MVC application with a POST request. The view that is launched also needs to post data back to itself in order to submit the data it collects for storage in a database. So I end up with a View with two HttpPost flagged methods in my controller (MVC throws an error that there are ambiguous Create methods).
So in the code below Create() would be posted to from the external application. Create(FormCollection collection) would be posted to when a displayed View is submitted.
//POST: /Application/Create
[HttpPost]
public ActionResult Create()
{
MyModel model = new MyModel();
//Parse External Data to model from Request.InputStream
return View(Model);
}
//POST: /Application/Create
[HttpPost]
public ActionResult Create(FormCollection collection)
{
//Save form collection data to database
return RedirectToAction("Index");
}
So long story short, how can I post data to an MVC application to launch a view, without getting an error for an ambiguous call.
Thanks.

in the first case when the post method comes in from the outside:
return View("ConfirmCreate", model)
Then create an action method named ConfirmCreate. After ConfirmCreate is called the second time you will redirect back to Index as you have.

So I was able to do this by changing the POST call to load the application to a PUT To avoid have duplicate post endpoints), then sending the PUT from an ajax call in another application and replacing the current document with the returned html from the successful ajax call. Thanks for the suggestions.

Related

MVC avoid page refreshing multiple adding

The action in my controller add an item to the DB,
I have to avoid the the page refreshing permit to insert multiple istance on the DB.
My url is:
/Create/?order=123
Is it possible to return the view without the parameters?
In this way the page refres will not call the create method.
Most correct way - create and modify entity by means of POST method.
[HttpPost]
public ActionResult Create(someModel model)
{
...
return View("differentView",model);
}
And If you follow this strategy is not to encounter this problem

handle direct url with history api in asp.mvc

I have my site like http://mysite.com/ and on the index page i have search box and for the result i am using jqgrid. When user click row in the jqgrid row I am taking data from cells and do ajax call to server and fetch json data and once data arrived I hide the search box and jqgrid and show another div which is I kept for result. In short, user will be on the same page just div's hide/show.
Now I have seen history api and used pushState and popstate so my url becomes in the addressbar like http://mysite.com/controller/action/para1/para2 (here para1 and para2 are the parameters i am passing to action). Everything is ok so far.
Now the problem is if I copy this URL "http://mysite.com/controller/action/para1/para2" and if I open this with let's say different browser and hit enter it display just json data. So, I am confused that how to handle when user directly use that url in controller.
I was thinking to check in the controller action if the request is AJAX then return json data otherwise full page, is that right approach? OR something on the client side we have so that it load the same way as earlier.
Thanks
if I copy this URL "http://mysite.com/controller/action/para1/para2" and if I open this with let's say different browser and hit enter it display just json data.
it only display json data because its ajax call only so how to deal with that so that it also display the same page even user directly access the url.
I think what you're looking for is Request.IsAjaxRequest():
public class FooController : Controller {
public ActionResult GetFoo(int id) {
var model = _fooService.Get(id);
if (Request.IsAjaxRequest())
return PartialView("_Foo", model);
return View("Foo", model);
}
}
Note: It's recommended to use WebAPI controllers to handle only json data. So if the user got there by typing the url the mvc controller will handle it and if you need to get the json data for that view you could call the webapi controller.
Use a separate controller or action method for AJAX and for Views. The View controller should match the URL. The Ajax controller should be the less "pretty" URL since it's behind the scenes.
You need to set up a routing definition in global.asax (MVC 3) or App_Start/RouteConfig.cs (MVC 4) to handle the parameters if you haven't already done that.
routes.MapRoute(
"MyRoute",
"MyUrlController/{action}/{para1}/{para2}",
new
{
action = "Index",
para1 = UrlParameter.Optional,
para2 = UrlParameter.Optional
}
);
Then in the View controller:
public ActionResult Index(string para1 = "Default Value", string para2 = "Default Value")
{
// ...Handle parameters...
return View("_MyView", viewModel);
}
Returning a View object type is the key. The History API URL doesn't get it's data from the same AJAX source controller which returns a PartialViewResult.

Why does RedirectToAction have no effect

When the method with the barcode parameter is called, RedirectToAction has absolutely no effect. I can see that it does indeed return to that route in the URL, but the model is not refreshed and it displays stale data.
In the SQL Server profiler I can see that the call isn't being made to pull back the new data.
How can I force this to happen?
Incidently, the call to: public ActionResult SRScanItem(string barcode) is itself the result of a RedirectToAction from another controller.
I have handful of calls to RedirectToAction("SRPickCollectionItems") elsewhere in the same controller and these all work fine.
Any idea what may be causing this?
public ActionResult SRPickCollectionItems()
{
IEnumerable<ISRPickingItemSummary> items =
SRPickingItemsViewModel.
GetDisplayableChunk(ApplicationState.CollectionId.ToString(),
ApplicationState.AssistantNumber);
return View(items);
}
public ActionResult SRScanItem(string barcode)
{
DataLayer.Instance.AddStockroomFoundItem(barcode, ApplicationState.CollectionId, ApplicationState.AssistantNumber);
return RedirectToAction("SRPickCollectionItems");
}
Maybe the redirect is going to a cached page.
Could you try and decorate SRPickCollectionItems with
[OutputCache(Duration = 0)]
You don't seem to returning to a post method, only a get so it is not obvious how the method with the Redirect is getting called unless you are send the barcode as a query string parameter in a get call through an actionlink or link tag.
Normally you would have two methods named SRPickCollectionItems. The Get method (which you already have) loads the view and the post method (that you are missing) processes the postback. The post method would be thus...
[HttpPost]
public ActionResult SRPickCollectionItemsstring barcode){
DataLayer.Instance.AddStockroomFoundItem(barcode, ApplicationState.CollectionId, ApplicationState.AssistantNumber);
return RedirectToAction("SRPickCollectionItems");
}

MVC & ajax: Should I create more views?

I'm developing an MVC3 application with EF and I wanted to make the UI fluent using jQuery ajax, the user will be able to navigate through the url, if he knows it or maybe he might receive a link pointing to a particular route, but, once the page is fully loaded it needs to be fluent, so I came up with one idea and I would like to discuss it here before I make the changes to the solution.
Here is what I came up with:
TestController.cs (Methods code has been omitted for simplicity)
public ActionResult Index() { ... }
public ActionResult Create() { ... }
[HttpPost]
public ActionResult Create(Test test) { ... }
public ActionResult Update(int testID) { ... }
[HttpPost]
public ActionResult Update(Test test) { ... }
public ActionResult Delete(int testID) { ... }
[HttpPost]
public ActionResult Delete(Test test) { ... }
So far it looks like most controllers. My views are as follows:
Views\Test\List.cshtml
Views\Test\Create.cshtml
Views\Test\Details.cshtml
Views\Test\Delete.cshtml
Now since I wanted to do it async: I've changed my List view so I could add, modify and remove from the list, so far is working like a charm. Plus, the user could still be able to navigate through the application using the url's, note that every link inside the application will perform an ajax request to do the actual work, there are no Route/Action links.
By now the application is working as expected, but now I came across something: there are views that I need to be ActionResult and PartialViewResult, that is because the user could type in the url: "/Admin/Test", which should return the full page, or could click on an anchor which will load only the content of the "/Admin/Test" and display it. To avoid the famous page inside page errors I wrote a function to send the request, and when the request arrives it selects only what I need, avoiding then the page inside page, and to duplicate views, but, the response is the whole page which, I don't need to say, it's not the best option, but since the application will be used by lan I didn't care too much about the payload of the response, but then I needed to write javascript code inside the views, so my solution was like null because using the jQuery selector to get only what I need the javascript wasn't there.
As for my new solution to solve my last solution:
I thought I might leave the original view as is, and create another view appending the word "Partial" after the original name, creating another method in the controller with the same naming convention, plus adding the new Route to my Route Table.
To wrap things up, what I need is the following:
- If the user types in "/Test" the response should be the entire page, loaded like the old days, screens flashing white and such.
- But if the user clicks the Test link in the navigation bar, the response should be async and refreshing only the content of my layout.
Any ideas? thoughts? suggestions?
In your actionmethod you can have
if (Request.IsAjaxRequest())
return PartialView("_somePartialView");
else
return PartialView("_someOtherPartialView");

Persisting model data on form post when redisplaying the view for an invalid ModelState

Simplified example:
[HttpGet]
public ActionResult Report(DateTime? date)
{
if (!date.HasValue)
{
date = DateTime.Now;
}
// Clear the ModelState so that the date is displayed in the correct format as specified by the DisplayFormat attribute on the model
ModelState.Clear();
// Expensive call to database to retrieve the report data
ReportModel model = DataAdapter.Convert(this.reportService.GetReport((DateTime)date));
// Store in TempData in case validation fails on HttpPost
TempData["ReportModel"] = model;
return View(model);
}
[HttpPost]
public ActionResult Report(ReportModel model)
{
if (ModelState.IsValid)
{
return RedirectToAction("Report", new { date = model.Date });
}
else
{
// Load the report from TempData, and restore again in case of another validation failure
model = TempData["ReportModel"] as ReportModel;
TempData["ReportModel"] = model;
// Redisplay the view, the user inputted value for date will be loaded from ModelState
return View(model);
}
}
My question is, am I going about this the right way by storing the report data in TempData? The code seems a little strange especially reading from and then writing back to TempData in the HttpPost action method to ensure it persists the next request.
Other options I can think of are:
(1) Make another call to the service layer from the HttpPost action (I'd rather not make another database call because of a validation failure just to redisplay the form as it seems inefficient). I guess I could implement caching at the service layer to avoid the database round trip...
(2) Use hidden inputs in the form (yuk!).
(3) Store the most recently viewed report in session permanently.
How is everyone else doing this sort of thing? What's the recommended practice?
My question is, am I going about this the right way by storing the report data in TempData?
No, absolutely not. Store something into TempData if and only if you redirect immediately afterwards as TempData survivces only a single redirect. If you store something into TempData in your GET action and then render a view, an AJAX request for example from this view would kill the TempData and you won't get the values back on your POST request.
The correct pattern is the following (no TempData whatsoever):
public ActionResult Report(DateTime? date)
{
if (!date.HasValue)
{
date = DateTime.Now;
}
// Clear the ModelState so that the date is displayed in the correct format as specified by the DisplayFormat attribute on the model
ModelState.Clear();
// Expensive call to database to retrieve the report data
ReportModel model = DataAdapter.Convert(this.reportService.GetReport((DateTime)date));
return View(model);
}
[HttpPost]
public ActionResult Report(ReportModel model)
{
if (ModelState.IsValid)
{
return RedirectToAction("Report", new { date = model.Date });
}
else
{
// Redisplay the view, the user inputted value for date will be loaded from ModelState
// TODO: query the database/cache to refetch any fields that weren't present
// in the form and that you need when redisplaying the view
return View(model);
}
}
(1) Make another call to the service layer from the HttpPost action
(I'd rather not make another database call because of a validation
failure just to redisplay the form as it seems inefficient). I guess I
could implement caching at the service layer to avoid the database
round trip...
That's exactly what you should do. And if you have problems with optimizing those queries or concerns of hitting your or something on each POST request cache those results. Databases are hyper optimized nowadays and are designed to do exactly this (don't abuse of course, define your indexes on proper columns and performance should be good). But of course caching is the best way to avoid hitting the database if you have a very demanding web site with lots of requests and users.
(2) Use hidden inputs in the form (yuk!).
Yuk, I agree but could work in situations where you don't have lots of them.
(3) Store the most recently viewed report in session permanently.
No, avoid Session. Session is the enemy of scalable and stateless applications.

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