Get selected radiobutton values in MVC

Question

I have below Model structure

public class Quiz
{
    public List<Question> Questions { get; set; }
}

public class Question
{
    public int Id { get; set; }
    public String QuestionText { get; set; }
    public List<Option> Options { get; set; }
    public int AnswerId { get; set; }
}

public class Option
{
    public int Id { get; set; }
    public String OptionText { get; set; }
    public int DisplayOrder { get; set; }
}

And my view is like below where I am displaying all the questions and options

foreach (var question in Model.Questions)
{
    @Html.DisplayFor(modelItem => question.QuestionText) <br />
    foreach (var option in question.Options)
    {
        @Html.RadioButton("Id", option.Id)@option.OptionText
    }
}
<input type="submit" value="Submit" />

I am not getting the values for all selected radiobuttons, It always returns one value in form collection

[HttpPost]
public ActionResult Quiz(Quiz userResponse, FormCollection form)
{
    foreach (var item in form.AllKeys)
    {
        string value = form[item];
        // save data 
    }
    //var selectedOption = frm["Id"];
    return View();
}

Can you please help?

Answer 1

You creating radio buttons that have no relationship to you model and all have the same name="Id" attribute (and you would only ever be able to select one option from all the questions). You need to use a for loop or EditorTemplate for typeof Question (refer this answer for a more detailed explanation). Using an EditorTemplate , your code will be

/Views/Shared/EditorTemplates/Question.cshtml

@model Question
@Html.HiddenFor(m => m.Id)
@Html.DisplayFor(m => m.QuestionText)
@foreach(var option in Model.Options)
{
    <div>
        <label>
            @Html.RadioButtonFor(m => m.AnswerId , option,Id, new { id = "" })
            <span>@option.OptionText</span>
        </label>
    </div>
}

and in the main view

@model Quiz
@using (Html.BeginForm())
{
    @Html.EditorFor(m => m.Questions)
    <input type="submit" value="Save" />
}

and the controller method

[HttpPost]
public ActionResult Quiz(Quiz model)

The model in the POST method will be bound with each question containing its Id and AnswerId (the Id of the selected Option ) properties.

Side note: Your current POST method has return View() but this would fail because the value of each Options property will be null . If you need to return the view (which should only be necessary if ModelState is invalid), then you need to repopulate those collections.