using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class Portfolio_Portfolio : System.Web.UI.Page
{
    string[] outerDataSource ={ "Outer Item 1", "Outer Item 2", "Outer Item 3" };
    string[] innerDataSource ={ "Inner Item 1", "Inner Item 2", "Inner Item 3" };

    protected void Page_Load(object sender, EventArgs e)
    {
        FillDataListOuter(DataListOuter);
    }

    private void FillDataListOuter(DataList dataListOuter)
    {
        dataListOuter.ItemCreated += new DataListItemEventHandler(DataListOuter_ItemCreated);
        dataListOuter.DataSource = outerDataSource;
        dataListOuter.DataBind();
    }

    void DataListOuter_ItemCreated(object sender, DataListItemEventArgs e)
    {
        if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
        {
            Label labelOuterItem = (Label)(e.Item.FindControl("LabelOuterItem"));
            labelOuterItem.Text = e.Item.DataItem.ToString();
            DataList dataListInner = (DataList)(e.Item.FindControl("DataListInner"));
            FillDataListInner(dataListInner);
        }
    }

    private void FillDataListInner(DataList dataListInner)
    {
        dataListInner.ItemCreated += new DataListItemEventHandler(dataListInner_ItemCreated);
        dataListInner.DataSource = innerDataSource;
        dataListInner.DataBind();
    }

    void dataListInner_ItemCreated(object sender, DataListItemEventArgs e)
    {
        if (e.Item.ItemType == ListItemType.Item || e.Item.ItemType == ListItemType.AlternatingItem)
        {
            Label labelInnerItem = (Label)(e.Item.FindControl("LabelInnerItem"));
            labelInnerItem.Text = e.Item.DataItem.ToString();
        }
    }
}