ASP.NET TreeView shows old datasource at 2:34 PM

I do not know what's wrong in my code: The TreeView always shows the old data source, although I assign a new data source to it.

My purpose: To show XML in a tree view. Each leaf element is in "element_name = element_value" format:

name
 |
 +-- first = F1
 |
 +-- last = L1

Here is a sample code:

Add a TreeView control to Default.aspx:

<asp:TreeView ID="xmlTreeView" runat="server"
OnTreeNodeDataBound="XmlTreeView_OnTreeNodeDataBound"
ShowLines="True" EnableViewState="False">

In code behind:

public partial class _Default : System.Web.UI.Page
{
  List<string> xmlStrList = new List<string>();

  protected void Page_Load(object sender, EventArgs e)
  {
      // Initiate XML data
      xmlStrList.Add("<name><first>F1</first><last>L1</last></name>");
      xmlStrList.Add("<name><first>F2</first><last>L2</last></name>");
      xmlStrList.Add("<name><first>F3</first><last>L3</last></name>");
      xmlStrList.Add("<name><first>F4</first><last>L4</last></name>");

      // Get random XML string
      int i = DateTime.Now.Second % xmlStrList.Count;

      // Create XmlDataSource
      XmlDataSource dataSource = new XmlDataSource();
      dataSource.Data = xmlStrList[i];

      // Bind XMLDataSource to tree view
      xmlTreeView.DataSource = dataSource;
      xmlTreeView.DataBind();
  }

  // To show leaf element in "element_name = element_value" format
  protected virtual void XmlTreeView_OnTreeNodeDataBound(Object sender, TreeNodeEventArgs e)
  {
      if (e.Node.DataItem is XmlElement)
      {
          XmlElement element = (XmlElement)e.Node.DataItem;
          if (!element.FirstChild.HasChildNodes)
          {
              e.Node.Text = e.Node.Text + " = " + element.InnerText;
          }
      }
  }
}

Everytime when I refresh the page, I get different XML string data source, but I see the SAME tree view data in browser! --- That is weird ...

I don't know why?

[Update] Copied from asp.net forum:
------------------------------------
This looks like a bug in the XmlDataSource control where modifying the Data property does not invalidate the cache. Setting EnableCaching=false is the workaround to use here.

Thanks,

Eilon
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