asp.net - How to bind database using LIST? -

Hello Iam trying to get database data and shown in RadTreeview, here I have got a sample, this sample is default As is the sample, every root and child will have to manually enter, but I want to bind the database, the values ​​are automatically filled (root / child)

I will show that example code ,

  list & lt; SiteDataItem & gt; SiteData = new list & lt; SiteDataItem & gt; (); SiteData.Add (new SiteDataItem (1, 0, "Product")); SiteData.Add (New SiteDataItem (2, 1, "RadControls for ASP.NET Ajax")); SiteData.Add (New SiteDataItem (3, 1, "Rad Controls for Silverlight")); SiteData.Add (New SiteDataItem (4, 2, "RadGrid")); SiteData.Add (new SiteDataItem (5, 2, "radheshubular")); SiteData.Add (New SiteDataItem (6, 2, "RadEditor")); SiteData.Add (New SiteDataItem (7, 3, "RadGrid")); SiteData.Add (New SiteDataItem (8, 3, "Radmannanu")); SiteData.Add (New SiteDataItem (9, 3, "RadEditor")); RadTreeView1. DataTextField = "Text"; RadTreeView1.DataFieldID = "ID"; RadTreeView1.DataFieldParentID = "ParentID"; RadTreeView1.DataSource = siteData; RadTreeView1.DataBind (); Please   
 
 
 Please try with the code snippet below.  
  Secure Zero Page_load (Object Sender, System.EventArgs e) {List & lt; TestModels & gt; Model = new list & lt; TestModels & gt; (); Model Add (New Test Model () {ID = 1, ParentID = null, text = "a1"}); Model Add (New Test Model) {ID = 2, ParentID = 1, text = "a2"}); Model Add (New Test Model () {ID = 3, ParentID = 2, text = "a3"}); Model Add (New Test Model () {ID = 4, ParentID = null, text = "a4"}); Model Add (New Test Model) {ID = 5, ParentID = 4, text = "a5"}); RadTreeView1.DataTextField = "Text"; RadTreeView1.DataFieldID = "ID"; RadTreeView1.DataFieldParentID = "ParentID"; RadTreeView1.DataSource = Model; RadTreeView1.DataBind (); }   
 class  
  public class testms {get public id ID { Set; } Public int? ParentID {Receive; Set; } Public string text {get; Set; }}   
  Please set zero to ParentID in place of 0.  Because this value assumes value 0. RadTreeView can not find any ID field with a value of 0.