MVC 4 - Return error message from Controller - Show in View

Question

I am doing a C# project using Razor in VS2010 (MVC 4). I need to return an error message from Controller to View and show it to the user. What I have tried:

CONTROLLER:

 [HttpPost]
 public ActionResult form_edit(FormModels model)
 {          
    model.error_msg = model.update_content(model);           
    ModelState.AddModelError("error", "adfdghdghgdhgdhdgda");
    ViewBag.error = TempData["error"];
    return RedirectToAction("Form_edit", "Form");

 }

VIEW:

@model mvc_cs.Models.FormModels
@using ctrlr = mvc_cs.Controllers.FormController


@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{

        <table>
        <tr>
        <td>       
        @Html.ValidationSummary("error")       
        @Html.ValidationMessage("error")      
        </td>
        </tr>
    <tr>
        <th>
            @Html.DisplayNameFor(model => model.content_name)
            @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")

        </th>
    </tr>
</table>

<table>
    <tr>
        <td>
            <input  type="submit" value="Submit" />
        </td>
    </tr>
</table>
}

Please help me to achieve this.

try return View(model) instead of return RedirectToAction("Form_edit", "Form"); — Grundy
– Grundy, Commented Nov 22, 2013 at 11:41
return view throws me a error while filling the drop down!!!! — user3021019
– user3021019, Commented Nov 25, 2013 at 5:27
after redirecting you will lose all data in ViewBag and etc. — Grundy
– Grundy, Commented Nov 25, 2013 at 5:35

dlght · Accepted Answer · 2013-11-27 21:12:23Z

The Return View(model) returns you error because you don't fill the model with the values in your post method and the model data for the dropdown is empty. Please provide the Get method to explain further how to manage displaying the error. In order to the error to be shown you should use this:

[HttpPost]
public ActionResult form_edit(FormModels model)
{          
   if(ModelState.IsValid())
   {
      --- operations 
      return Redirect("OtherAction", "SomeController");
   }

   // here you can use a little trick
   //fill the model property that holds the information for the dropdown with the data 

   // you haven't provided the get method but it should look something like this
   model.Countries = ... some data goes here;
   model.dd_value = ... some other data;
   model.dd_text = ... other data;

   ModelState.AddModelError("", "adfdghdghgdhgdhdgda");
   return View(model);
}

and then in the view just use :

@model mvc_cs.Models.FormModels
@using ctrlr = mvc_cs.Controllers.FormController


@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{

    <table>
    <tr>
    <td>       
    @Html.ValidationSummary(true)             
    </td>
    </tr>
<tr>
    <th>
        @Html.DisplayNameFor(model => model.content_name)
        @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")

    </th>
</tr>
</table>

<table>
<tr>
    <td>
        <input  type="submit" value="Submit" />
    </td>
</tr>
</table>
}

This should work okay.

If you just use RedirectToAction it will redirect you to the get method --> you will have no error but the view will be just reloaded and no error would be shown.

other way around is that you can pass the error not by ModelState.AddError, but with ViewData["error"] like this:

[HttpPost]
public ActionResult form_edit(FormModels model)
{          
   TempData["error"] = "someErrorMessage";
   return RedirectToAction("form_Post", "Form");
}

[HttpGet]
public ActionResult form_edit()
{
    do stuff here ----
    ViewData["error"] = TempData["error"];
    return View();
}

@model mvc_cs.Models.FormModels
@using ctrlr = mvc_cs.Controllers.FormController


@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{

    <table>
    <tr>
    <td>       
    <div>@ViewData["error"]</div>             
    </td>
    </tr>
<tr>
    <th>
        @Html.DisplayNameFor(model => model.content_name)
        @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")

    </th>
</tr>
</table>

<table>
<tr>
    <td>
        <input  type="submit" value="Submit" />
    </td>
</tr>
</table>
}

Rethic · Accepted Answer · 2014-04-17 18:21:00Z

Thanks for all the replies.

I was able to solve this by doing the following:

CONTROLLER:

[HttpPost]       
public ActionResult form_edit(FormModels model)
{
  model.error_msg = model.update_content(model);
  return RedirectToAction("Form_edit", "Form", model);
}

public ActionResult form_edit(FormModels model, string searchString,string id)
{
  string test = model.selectedvalue;
  var bal = new FormModels();
  bal.Countries = bal.get_contentdetails(searchString);
  bal.selectedvalue = id;
  bal.dd_text = "content_name";
  bal.dd_value = "content_id";

  test = model.error_msg;
  ViewBag.head = "Heading";

  if (model.error_msg != null)
  {
    ModelState.AddModelError("error_msg", test);
  }

  model.error_msg = "";
  return View(bal);
}

VIEW:

@using (Html.BeginForm("form_edit", "Form", FormMethod.Post))
{
  <table>
    <tr>
      <td>
        @ViewBag.error
        @Html.ValidationMessage("error_msg")
      </td>
    </tr>
    <tr>
      <th>
        @Html.DisplayNameFor(model => model.content_name)
        @Html.DropDownListFor(x => x.selectedvalue, new SelectList(Model.Countries, Model.dd_value, Model.dd_text), "-- Select Product--")
      </th>
    </tr>
  </table>
}

Matt Millican · Accepted Answer · 2013-11-27 13:21:14Z

3

If you want to do a redirect, you can either:

ViewBag.Error = "error message";

or

TempData["Error"] = "error message";

answered Nov 27, 2013 at 13:21

Matt Millican

4,0544 gold badges43 silver badges55 bronze badges

Comments

live-love · Accepted Answer · 2019-07-04 19:43:10Z

2

You can add this to your _Layout.cshtml:

@using MyProj.ViewModels;
...
    @if (TempData["UserMessage"] != null)
    {
        var message = (MessageViewModel)TempData["UserMessage"];
        <div class="alert @message.CssClassName" role="alert">
            <button type="button" class="close" data-dismiss="alert" aria-label="Close">
                <span aria-hidden="true">&times;</span>
            </button>
            <strong>@message.Title</strong>
            @message.Message
        </div>
    }

Then if you want to throw an error message in your controller:

    TempData["UserMessage"] = new MessageViewModel() { CssClassName = "alert-danger  alert-dismissible", Title = "Error", Message = "This is an error message" };

MessageViewModel.cs:

public class MessageViewModel
    {
        public string CssClassName { get; set; }
        public string Title { get; set; }
        public string Message { get; set; }
    }

Note: Using Bootstrap 4 classes.

edited Jul 4, 2019 at 19:43

answered Jul 4, 2019 at 19:34

live-love

53.2k27 gold badges257 silver badges220 bronze badges

1 Comment

Dimitri Over a year ago

very elegant ;)

Collectives™ on Stack Overflow

MVC 4 - Return error message from Controller - Show in View

4 Answers 4

Comments

Comments

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related