Question

I’m having problems getting the new data from the RandomNumbers List

I got this simple class

public class Test
{
    public string Name { get; set; }
    public List<int> RandomNumbers { get; set; }

    public Test()
    {
        RandomNumbers = new List<int>(){0,0,0,0,0};
    }
}

In my controller I have created two ActionResults one for Get and one for Post

public ActionResult Test()
{
    var test = new Test();
    return View(test);
}

[HttpPost]
public ActionResult Test(Test test)
{
    return View();
}

And Finally the View

@model Test
@{
    ViewBag.Title = "Test";
    Layout = null;
}

<h2>Test</h2>
@using (Html.BeginForm())
{
    @Html.LabelFor(model => model.Name)
    @Html.EditorFor(model => model.Name)
    <ul>@foreach (var t in Model.RandomNumbers)
        {
            <li> 
                @Html.LabelFor(model => t)
                @Html.EditorFor(model => t)
            </li>
        }
    </ul>
    <input type="submit" value="Save"/>
}

The Page looks like this.
Now when I’m clicking the Save button, the [HttpPost] Test is called, but the included Test Object only contains the new Name, none of the Changes from the RandomNumber list is included. What I’m doing wrong?

Answer 1

You have to make sure your nested collection gets rendered in the view accordingly.

In the view:

     <ul>@for (int i = 0; i < Model.RandomNumbers.Count; i++)
     {
            <li> 
                @Html.LabelFor(m => m.RandomNumbers[i])
                @Html.TextBoxFor(m => m.RandomNumbers[i])
            </li>
     }
     </ul>

This will create indexed input fields like

<input id="RandomNumbers_3_" name="RandomNumbers[3]" type="text" value="0" />

(skipped validation for brevity)