1,

2,categories.aspx.cs

private void Page_Load(object sender, System.EventArgs e)

{

string sql=@"select categoryname as Text,'products.aspx?catid='+ltrim(str(categoryid)) as TreeNodesrc

from categories as TreeNode for xml auto ,xmlData " ;

SqlConnection sqlConn=new SqlConnection("Server=dbm-1;Uid=sa;pwd=;DataBase=Northwind");

SqlCommand com=new SqlCommand (sql,sqlConn);

DataSet ds=new DataSet();

sqlConn .Open();

ds.ReadXml(com.ExecuteXmlReader(),XmlReadMode.Fragment );

sqlConn.Close();

sqlConn=null;

ds.DataSetName ="TREENODES";

ds.WriteXml(Response.OutputStream );

}