I have this api controller action that takes an object "ContentList" as parameter.
[HttpPost]
public List<string> SendList(string param, ContentList list)
{
List<string> testReturn = new List<string> { "test1", "test2", "test3", "test4" };
return testReturn ;
}
What I have tried so far is to call a controller action like this:
Uri _uri = new Uri("http://localhost:xxxxx/api/FakeTest/SendList?param=test");
var serializer = new JavaScriptSerializer();
string requestData = serializer.Serialize(new
{
list = ContentList,
});
using (var client = new WebClient())
{
client.Headers[HttpRequestHeader.ContentType] = "application/json";
var result = client.UploadData(_uri, Encoding.UTF8.GetBytes(requestData));
var tempString = Encoding.UTF8.GetString(result);
}
In this example, tempString = ["test1","test2","test3","test4"] as reurned by the controller action..
In the controller action, I can access the properties of the passed in ContentList, and return their values (changing the actions return value accordingly ofcourse).
However, in the controller action, I need to send off the ContentList object for further processing, and this seems to fail. I get a 500 internal server error, and I can't put a breakpoint in the controller to follow the values passed in. The debugger never hits it...
I expect this has something to do with sending json to the controller action.
Anyway, it seems that the ContentList is rejected by the code it is sent to from the controller action, so I figure I need to do some sort of de-serializing, right?
Bottomline, the question is, what is the correct way to call a controller action from code, pass in a C# object, and make it usable from the controller action?
If you are using MVC 3 your controller should be able to reveive and parse json data in a direct way. If you are using MVC 2 you'll need to register a new factory on your application to take care of json parsing on the controller
protected void Application_Start()
{
RegisterRoutes(RouteTable.Routes);
ValueProviderFactories.Factories.Add(new JsonValueProviderFactory());
}
More info on the subject here:
http://haacked.com/archive/2010/04/15/sending-json-to-an-asp-net-mvc-action-method-argument.aspx
Related
I use MVC 4 and have moved some logic into an authorize filter. I am trying redirect to an error page based on not being authorized. I would like to set the last page route and a few other properties to catch the error.
Below is my override
// handle unauthorized
protected override void HandleUnauthorizedRequest(AuthorizationContext filterContext)
{
filterContext.Controller.ViewBag.LastRoute = filterContext.RouteData;
filterContext.Controller.ViewBag.Issue = "put...val here";
var routeValues = new RouteValueDictionary(new
{
controller = "Error",
action = "Oops"
});
filterContext.Result = new RedirectToRouteResult(routeValues);
}
controller
[AllowAnonymous]
public ActionResult Oops()
{
var m = new Core.Models.ErrorModel();
var v = ViewBag.Issue; // == null
return View("~/Views/Error/Oops.cshtml", m);
}
I tried how to set values to viewbag in actionfilterattribute asp mvc 5 for action filters and it works
Any help would be appreciated.
EDIT:
Sorry when I get to the controller the value for:
ViewBag.Issue = null.
I'm not sure how to set the property and have it hold value.
RedirectToRouteResult is going to send a redirect response to the browser and browser will issue a brand new GET request to the url specified. ViewBag data do not survive between 2 http requests.
You may use TempData which will keep the data between 2 seperate http requests. You can set your TempData value in one action method and any action method that is called after this can get values from the TempData object and then use it. TempData use Session behind the scene to store data. The value of TempData persists until it is read or until the session times out. This is ideal for scenarios such as redirection because the values in TempData are available beyond a single request.
So in your action filter you can set the TempData dictionary instead of ViewBag.
filterContext.Controller.TempData["Issue"] = "Robots are laughing non stop";
var routeValues = new RouteValueDictionary(new
{
controller = "Home",
action = "Oops"
});
filterContext.Result = new RedirectToRouteResult(routeValues);
Now in your Oops action method, you may read the TempData value you set
public ActionResult Oops()
{
var issueDetails = TempData["Issue"];
// TO DO : Do something useful with issueDetails :)
return View();
}
Keep in mind that TempData values won't be available after you read it. So if you want to read it in your view again, set it again or better use a view model and set the already read value as the property value of your view model.
In the RedirectToAction below, I'd like to pass a viewmodel. How do I pass the model to the redirect?
I set a breakpoint to check the values of model to verify the model is created correctly. It is correct but the resulting view does not contain the values found in the model properties.
//
// model created up here...
//
return RedirectToAction("actionName", "controllerName", model);
ASP.NET MVC 4 RC
RedirectToAction returns a 302 response to the client browser and thus the browser will make a new GET request to the url in the location header value of the response came to the browser.
If you are trying to pass a simple lean-flat view model to the second action method, you can use this overload of the RedirectToAction method.
protected internal RedirectToRouteResult RedirectToAction(
string actionName,
string controllerName,
object routeValues
)
The RedirectToAction will convert the object passed(routeValues) to a query string and append that to the url(generated from the first 2 parameters we passed) and will embed the resulting url in the location header of the response.
Let's assume your view model is like this
public class StoreVm
{
public int StoreId { get; set; }
public string Name { get; set; }
public string Code { set; get; }
}
And you in your first action method, you can pass an object of this to the RedirectToAction method like this
var m = new Store { StoreId =101, Name = "Kroger", Code = "KRO"};
return RedirectToAction("Details","Store", m);
This code will send a 302 response to the browser with location header value as
Store/Details?StoreId=101&Name=Kroger&Code=KRO
Assuming your Details action method's parameter is of type StoreVm, the querystring param values will be properly mapped to the properties of the parameter.
public ActionResult Details(StoreVm model)
{
// model.Name & model.Id will have values mapped from the request querystring
// to do : Return something.
}
The above will work for passing small flat-lean view model. But if you want to pass a complex object, you should try to follow the PRG pattern.
PRG Pattern
PRG stands for POST - REDIRECT - GET. With this approach, you will issue a redirect response with a unique id in the querystring, using which the second GET action method can query the resource again and return something to the view.
int newStoreId=101;
return RedirectToAction("Details", "Store", new { storeId=newStoreId} );
This will create the url Store/Details?storeId=101
and in your Details GET action, using the storeId passed in, you will get/build the StoreVm object from somewhere (from a service or querying the database etc)
public ActionResult Details(string storeId)
{
// from the storeId value, get the entity/object/resource
var store = yourRepo.GetStore(storeId);
if(store!=null)
{
// Map the the view model
var storeVm = new StoreVm { Id=storeId, Name=store.Name,Code=store.Code};
return View(storeVm);
}
return View("StoreNotFound"); // view to render when we get invalid store id
}
TempData
Following the PRG pattern is a better solution to handle this use case. But if you don't want to do that and really want to pass some complex data across Stateless HTTP requests, you may use some temporary storage mechanism like TempData
TempData["NewCustomer"] = model;
return RedirectToAction("Index", "Users");
And read it in your GET Action method again.
public ActionResult Index()
{
var model=TempData["NewCustomer"] as Customer
return View(model);
}
TempData uses Session object behind the scene to store the data. But once the data is read the data is terminated.
Rachel has written a nice blog post explaining when to use TempData /ViewData. Worth to read.
Using TempData to pass model data to a redirect request in Asp.Net Core
In Asp.Net core, you cannot pass complex types in TempData. You can pass simple types like string, int, Guid etc.
If you absolutely want to pass a complex type object via TempData, you have 2 options.
1) Serialize your object to a string and pass that.
Here is a sample using Json.NET to serialize the object to a string
var s = Newtonsoft.Json.JsonConvert.SerializeObject(createUserVm);
TempData["newuser"] = s;
return RedirectToAction("Index", "Users");
Now in your Index action method, read this value from the TempData and deserialize it to your CreateUserViewModel class object.
public IActionResult Index()
{
if (TempData["newuser"] is string s)
{
var newUser = JsonConvert.DeserializeObject<CreateUserViewModel>(s);
// use newUser object now as needed
}
// to do : return something
}
2) Set a dictionary of simple types to TempData
var d = new Dictionary<string, string>
{
["FullName"] = rvm.FullName,
["Email"] = rvm.Email;
};
TempData["MyModelDict"] = d;
return RedirectToAction("Index", "Users");
and read it later
public IActionResult Index()
{
if (TempData["MyModelDict"] is Dictionary<string,string> dict)
{
var name = dict["Name"];
var email = dict["Email"];
}
// to do : return something
}
Another way to do it is to store it in the session.
var s = JsonConvert.SerializeObject(myView);
HttpContext.Session.SetString("myView", s);
and to get it back
string s = HttpContext.Session.GetString("myView");
myView = JsonConvert.DeserializeObject<MyView>(s);
I am writing an application wherein I need to send a System.Collections.ArrayList data as a parameter from one controller action to another.
I am using
return RedirectToAction("action1","controller1", new { arrList = arrListInFirstAction});
But since the ArrayList goes out of scope in the first action, the parameter in the redirected to action receives a null parameter.
Can someone please help me find an answer to this problem.
Thanks.
you can not send complex types as route parameters. you can, however, use TempData collection to keep that object for one request and on next request it will be automatically removed from collection
publci ActionResutl action()
{
TempData["arr"] = new int[]{1,2,3};
return RedirectToAction("action1");
}
Public ActionResult action1()
{
int[] arr = TempData["arr"];
return View();
}
How can i pass the json output from controller action to its view ?
As I tried to send before, My code is :
public ActionResult Index()
{
Guid Id = new Guid("66083eec-7965-4f3b-adcf-218febbbceb3");
List<TasksToOfficer> officersTasks = tasks_to_officer_management.GetTasksToOfficers(Id);
return Json(officersTasks)
}
it is asking for JsonRequestBehavior.AllowJson like parameter. I know it is new in asp.net mvc 2 but as redirect to view there is nothis happens but asking for download the json output file. I want to work with returned data in my jQuery .But something going wrong there. and if I removed the parameter then it is showing error :
This request has been blocked because sensitive information could be disclosed to third party web sites when this is used in a GET request. To allow GET requests, set JsonRequestBehavior to AllowGet.
How to avoid this and get json data at view ?
Here is an example of what you are trying to do. First in your view you call $.getJSON to grab the JSON data from the action:
$.getJSON('/Data/StockQuote', function(data) {
if (data.success) {
ShowStockQuote(data);
}
});
Then your action will look like this:
public JsonResult GetStockQuote()
{
JsonResult result = new JsonResult()
{
Data = new {
lastTradePrice = 50,
lastUpdated = "10/1/2010",
expirationDate = "10/2/2010",
success = true
},
JsonRequestBehavior = JsonRequestBehavior.AllowGet
};
return result;
}
Once the JSON data is returned from your action to the $.getJSON you can use data to access all the values off of the JSON object. So data.success will give you the success and so forth.
I am creating a modular ASP.NET MVC application using areas. In short, I have created a greedy route that captures all routes beginning with {application}/{*catchAll}.
Here is the action:
// get /application/index
public ActionResult Index(string application, object catchAll)
{
// forward to partial request to return partial view
ViewData["partialRequest"] = new PartialRequest(catchAll);
// this gets called in the view page and uses a partial request class to return a partial view
}
Example:
The Url "/Application/Accounts/LogOn" will then cause the Index action to pass "/Accounts/LogOn" into the PartialRequest, but as a string value.
// partial request constructor
public PartialRequest(object routeValues)
{
RouteValueDictionary = new RouteValueDictionary(routeValues);
}
In this case, the route value dictionary will not return any values for the routeData, whereas if I specify a route in the Index Action:
ViewData["partialRequest"] = new PartialRequest(new { controller = "accounts", action = "logon" });
It works, and the routeData values contains a "controller" key and an "action" key; whereas before, the keys are empty, and therefore the rest of the class wont work.
So my question is, how can I convert the "/Accounts/LogOn" in the catchAll to "new { controller = "accounts", action = "logon" }"??
If this is not clear, I will explain more! :)
Matt
This is the "closest" I have got, but it obviously wont work for complex routes:
// split values into array
var routeParts = catchAll.ToString().Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
// feels like a hack
catchAll = new
{
controller = routeParts[0],
action = routeParts[1]
};
You need to know what part is what in the catchAll parameter. Then you need to parse it yourself (like you are doing in your example or use a regexp). There is no way for the framework to know what part is the controller name and what is the action name and so on, as you haven't specified that in your route.
Why do you want to do something like this? There is probably a better way.