CODEWITHSUNDEEP
asp.net-mvc-3postback
Lalit
Lalit

Reputation: 352

MVC3: Updated value does not reflect in text box after post

I am showing a collection of data on my page. I am showing label and Textbox for each row.

Below is the sample code from my View:

@using (Html.BeginForm())
{
   <input type="submit" value="Ok" />
   @for (int index = 0; index < Model.Persons.Count; index++ )
   {
      @Model.Persons[index].Name
      @Html.TextBoxFor(m => Model.Persons[index].Amount)
   }
}

In the Post Action, I am update Amount (say increasing by 5). 

    [HttpPost]
    public ActionResult Persons(PersonList presenter)
    {

        for (int index = 0; index < presenter.Persons.Count; index++)
        {
            presenter.Persons[index].Amount += 5;
        }
        return View(presenter);
    }

This updated amount is not reflected on the page. However if I use below code then it is shown properly, like 

@Model.Persons[index].Amount

Or

<input type="text" id=@("Persons_" + index + "__Amount") name="Persons[@index].Amount " value="@Model.Persons[index].Amount" ></input>

I would like to the reason for such behaviour that why is it happening?

Any help would be appreciated.

Upvotes: 1

Views: 2832

Answers (2)

Gokulnath
Gokulnath

Reputation: 1256

Before updating the values, just add ModelState.Clear(), update your collection and return it.

Upvotes: 5

Chris Pont
Chris Pont

Reputation: 791

The posted values will override the viewmodel values. I've had a workaround for this before using...

ModelState["Field"].Value = new ValueProviderResult("NewValue", "Field", CultureInfo.InvariantCulture);

I guess in your case (and I'm not entirely sure what your object is) something along the lines of

PersonCollection persons = (PersonCollection)ModelState["Persons"].Value.RawValue;
persons[index].Amount += 5;
ModelState["Persons"].Value = new ValueProviderResult(persons, "Persons", CultureInfo.InvariantCulture);

Upvotes: 2

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