dynamically created radiobuttonlist "not declared"

Question

I am dynamically creating a table which places a dynamically created radiobuttonlist in each row.

I then want to display the results on the page when the submit button is clicked.

I am getting an error message stating that

'question1' is not declared

Why might this be happening?? I've included all my code below.

Code behind:

Sub Page_Load(ByVal Sender as Object, ByVal E as EventArgs)

    For i As Integer = 1 To 3
        Dim TableRow As New TableRow()
        Dim TableRowCell_1 As New TableCell()
        TableRowCell_1.Text = i
        Dim TableRowCell_2 As New TableCell()

        TableRow.Cells.Add(TableRowCell_1)
        TableRow.Cells.Add(TableRowCell_2)
        QuestionnaireTable.Rows.Add(TableRow)

        Dim question As New RadioButtonList
        question.ID = "question" & i
        question.RepeatColumns = "2"
        question.Items.Insert(0, new listitem("", "1"))
        question.Items.Insert(1, new listitem("", "2"))
        TableRowCell_3.Controls.Add(question)
    Next

End Sub

Sub btnSendFeedback_Click(sender as Object, e as EventArgs)
    Dim question1 As RadioButtonList = DirectCast(Page.FindControl("question1"), RadioButtonList)
    Dim question2 As RadioButtonList = DirectCast(Page.FindControl("question2"), RadioButtonList)
    Dim question3 As RadioButtonList = DirectCast(Page.FindControl("question3"), RadioButtonList)
    Response.write(question1.SelectedValue & " - " & question2.SelectedValue & " - " & question3.SelectedValue)
End Sub

Body:

<asp:Table runat="server" ID="QuestionnaireTable" />

<asp:Button OnClick="btnSendFeedback_Click" runat="server" Text="Submit..." ID="submitbutton" />    

Answer 1

When you declare your controls in the markup, Visual Studio and ASP.NET make it so that you can access that control in the code-behind.

When you declare a control dynamically like this, you have to make accessible from the code-behind.

There are multiple ways to do this, probably the easiest is:

Dim question1 As RadioButtonList = DirectCast(Page.FindControl("question1"), RadioButtonList)