edit xml in xmldatasource

edit xml in xmldatasource

protected void Page_Load(object sender, EventArgs e)
{
//UpdatableXmlDataSource1.FilterXPath = "contents/content[@position='test']/htmlcode[@language='english']";
XmlDataSource1.XPath = "contents/content[@position='test']/htmlcode[@language='english']";
}
protected void Button1_Click(object sender, EventArgs e)
{
XmlNode node = XmlDataSource1.GetXmlDocument().SelectSingleNode("contents/content[@position='test']/htmlcode[@language='english']");
node.InnerText = "hihi";
XmlDataSource1.Save();
}