How to build an ASP.NET TreeView From Scratch...?

Question

I am trying to build a nested/threaded comment system in ASP.NET. I don't know how the PHP guys do it. Its much harder than first imagined.

I am trying my damnedest get Hierarchical data to output to the user, but its not working.

I have a table with text, a itemID and a parentID.

I want to display the information in a tree view format, but asp.net's standard control just doesn't work...

Can anyone point me in the right direction of how to output this into a treeview. I have tried nesting repeaters, straight out html building from codebehind and the treeview control.

I still haven't found a solution... Can anyone help me out?

Answer 1

Quickly, by head (could not check in VS2k8 now), I would do it something like this using Linq to SQL

private void BuildTree()
{
   List<Item> items = from item in dataContext.Items
                      select item;

   List<Item> rootItems = items.FindAll(p => p.ParentID == null );

   foreach ( Item item in rootItems )
   {
      TreeViewNode tvi = new TreeViewNode(item.text);
      BuildChildNodes(tvi, items, item.ID);
      YourTreeNodeName.Nodes.Add(tvi);
   }   
}

private void BuildChildNodes(TreeViewNode parentNode, List<Item> items, long parentID)
{
   List<Item> children = items.FindAll ( p => p.ParentID = parentID );
   foreach( Item item in children)
   {
      TreeViewNode tvi = new TreeViewNode(item.text);
      parentNode.Nodes.Add(tvi);
      BuildChildNodes(tvi, items, item.ID);         
   }
}