Add ability to provide list items to composite control with DropDownLIst

Question

I'm creating a composite control for a DropDownList (that also includes a Label).

The idea being that I can use my control like a dropdown list, but also have it toss a Label onto the page in front of the DDL.

I have this working perfectly for TextBoxes, but am struggling with the DDL because of the Collection (or Datasource) component to populate the DDL.

Basically I want to be able to do something like this:

<ecc:MyDropDownList ID="AnimalType" runat="server" LabelText="this is what will be in the label">
<asp:ListItem Text="dog" Value="dog" />
<asp:ListItem Text="cat" Value="cat" />
</ecc:MyDropDownList>

The problem is, I'm not extending the DropDownList class for my control, so I can't simply work it with that magic. I need some pointers to figure out how I can turn my control (MyDropDownList), which is currently just a System.Web.UI.UserControl, into something that will accept List items within the tag and ideally, I'd like to be able to plug it into a datasource (the same functions that the regular DDL offers).

I tried with no luck just extending the regular DDL, but couldn't get the Label component to fly with it.

Answer 1

After doing some digging and searching I found a solution that works. Hopefully this will help someone else out in the future:

[ParseChildren(true, "Items")]
public class EDropDownList : CompositeControl, IValidatedFields
{
    public string PromptingText { get; set; }
    public string Value { get; set; }
    public Label __Label { get; set; }
    private ListItemCollection _items;
    public DropDownList __DropDownList;
    public ListItemCollection Items 
    {
        get { return _items; }
        set
        {
            if (_items != value)
            {
                _items = value;
            }
        }
    }

    public string Type { get { return "DropDownList"; } }


    public EDropDownList()
    {
        __Label = new Label();
    }
    protected override void CreateChildControls()
    {
        __DropDownList = new DropDownList();
        foreach (ListItem myItem in _items)
        {
            __DropDownList.Items.Add(myItem);
        }
        Controls.AddAt(0, __Label);
        Controls.AddAt(1, __DropDownList);
    }

    protected override void OnLoad(EventArgs e)
    {
        // label section            
        __Label.Text = PromptingText+"<br />";
        __Label.ForeColor = Color.Red;
        __Label.Visible = false;
        // ddl section
        if (Page.IsPostBack)
            Value = __DropDownList.SelectedValue;
    }
}