无法在ASP.NET Repeater模板中填充RadioButtonList

Question

I am trying to populate a repeater containing a label and a RadioButtonList in an ASP.NET webform to make a small quiz.

These are the classes I am using:

public class Option
{
    private string _body;
    private bool? _isCorrect;

    #region properties
    public string Body
    {
        get { return _body; }
    }

    public bool? IsCorrect
    {
        get { return _isCorrect; }
    }

    #endregion

    #region constructors

    public Option(string body)
    {
        _body = body;
        _isCorrect = null;
    }

    public Option(string body, bool isCorrect)
    {
        _body = body;
        _isCorrect = isCorrect;
    }
    #endregion

    #region methods

    public override string ToString()
    {
        return _body;
    }

    #endregion

}

and:

public class Question
{
    private string _body;
    private Option[] _optionsArray;
    private List<Option> _optionsList;

    #region properties

    public string Body
    {
        get { return _body; }
    }

    public Option[] Options
    {
        get { return _optionsArray; }
    }

    public List<Option> OptionsList
    {
        get { return _optionsList; }

    }
    #endregion


    #region constructors

    public Question(string body, Option[] options)
    {
        _body = body;

        _optionsArray = options;

        _optionsList = new List<Option>();
        foreach (Option opt in options)
        {
            _optionsList.Add(opt);
        }
    }

    #endregion

    #region methods

    public override string ToString()
    {
        return _body;
    }

    public List<Option> GetOptions()
    {
        return OptionsList;
    }

    #endregion

}

My webform looks like this:

<div runat="server" ID="quizDiv">



    <br />
    <br />

    <asp:Repeater ID="Repeater1" runat="server">
        <ItemTemplate>
            <%--<asp:Label ID="questionBody" runat="server" Text=<%# DataBinder.Eval(Container.DataItem, "Body") %>>--%>
            <asp:Label ID="questionBody" runat="server" Text=<%# ((Question)Container.DataItem).Body %>>
            <asp:radiobuttonlist ID="blah" runat="server" DataTextField="Body" DataValueField="Body" DataSource=<%# ((Question)Container.DataItem).OptionsList %> >

            </asp:radiobuttonlist>  
            </asp:Label>
        </ItemTemplate>
    </asp:Repeater>
    <br />


</div>

and the code-behind like so:

protected void btnStart_Click(object sender, EventArgs e)
    {
        Dataset1 ds = new Dataset1();
        question = ds.CreateQuestion();

        List<Question> qts = new List<Question>();
        qts.Add(question);

        Repeater1.DataSource = qts;
        Repeater1.DataBind();

    }

For the time being I am just using one question. The label displaying my question shows up fine, but no radio buttons show up for displaying the answer options. I have gone through many samples, and this seems to work for people when they use data from a DB via a DataTable or DataSet. However no matter how much I to play around with the Datasource, DataValueField and DataTextField parameters the RadioButtonList remains utterly barren. As you can see, I initially used an array of Option and also tried a List but to no avail.

What am I missing here?

---

EDIT - Found my mistake I had the <asp:label> and <asp:radiobuttonlist> tags nested wrong! The label was encapsulating the radiobuttonlist and causing the problem from what I can make out.

---

ALTERNATIVE - thanks to balexandre

balexandre did provide a workable alternative by using only code-behing. Thank you!

I am including the code listing of this alternative for anyone who needs it and happens across this post.

Change the markup to look like this:

protected void Repeater1_ItemDataBound(Object Sender, RepeaterItemEventArgs e)
    {

        if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
        {

            RadioButtonList rbl = (RadioButtonList)e.Item.FindControl("blah");
            // do anything with your rbl
            foreach (Option opt in question.Options)
            {
                rbl.Items.Add(opt.ToString());
            }
        }
    }  

and the code-behind must have the event handler:

 protected void Repeater1_ItemDataBound(Object Sender, RepeaterItemEventArgs e) { if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem) { RadioButtonList rbl = (RadioButtonList)e.Item.FindControl("blah"); // do anything with your rbl foreach (Option opt in question.Options) { rbl.Items.Add(opt.ToString()); } } } 

Answer 1

you can only access the template using the Repeater method OnItemDataBound witch is invoked before it draws anything to the page.

void Repeater1_ItemDataBound(Object Sender, RepeaterItemEventArgs e) {

    if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem) {

        RadioButtonList rbl = (RadioButtonList)e.Item.FindControl["blah"];
        // do anything with your rbl

    }
}    

Or by looping through all the Controls in the Repeater Collection, witch for example you have submited the page.

---

BTW, and just for your information

this code:

private string _body;
private bool? _isCorrect;

public string Body
{
    get { return _body; }
}

public bool? IsCorrect
{
    get { return _isCorrect; }
}

is the same as

public string Body { private get; }
public bool? IsCorrect { private get; }