Hi, i was looking around for an article on how to extend the repeater control to add an empty data template similar to the GridView control.  Here is a link to the the article i found.  However i discovered that it rendered the header and footer, so i set about creating my own one and come up with the following:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace ControlLibrary
{
  public class Repeater : System.Web.UI.WebControls.Repeater
  {
  private ITemplate _emptyDataTemplate;[Browsable(false)]
  [PersistenceMode(PersistenceMode.InnerProperty)]
  public ITemplate EmptyDataTemplate
  {
  get { return _emptyDataTemplate; }
  set { _emptyDataTemplate = value; }
  }protected override void Render(HtmlTextWriter output)
  {
  // If there is no data then we don't wish to render anything (including the header and the footer)
  if (this.Items.Count == 0)
  {
  // If an empty data template has been provided then display it
  if (this.EmptyDataTemplate != null)
  {
  PlaceHolder phdTemplate = new PlaceHolder();
  this.EmptyDataTemplate.InstantiateIn(phdTemplate);
  phdTemplate.RenderControl(output);
  }
  }
  else
  base.Render(output);
  }
  }
}

Now all you have to do is say:


<%@ Register TagPrefix=”Flixon” Namespace=”ControlLibrary” Assembly=”ControlLibrary” %>
<Flixon:Repeater>
    <ItemTemplate>
          <%# Container.DataItem %>
    </ItemTemplate>
    <EmptyDataTemplate>
         No data returned!
    </EmptyDataTemplate>
</Flixon:Repeater>


on your page and you’re done.

I hope this helps.

Hi, i recently ran in to a situation where i had to return every article in my database that was under a particular category (including all articles within the sub categories, sub sub categories and so on).  The Categories table relates a sub category to a category by a ParentID.

At first i went along the lines of a recursive sql statement but this caused problems when there was no articles in one of the top level categories (not an easy problem to spot).  The solution i finally come up with was one i particularly like as it meant i did not have to modify my query much.  I simply add the following function:

CREATE FUNCTION [dbo].[GetCategories]
 (
 @ParentID INT,
 @Output VARCHAR(255)
 )
RETURNS VARCHAR(255)
AS
BEGIN
 IF @Output = ''
 BEGIN
  SET @Output = Convert(VARCHAR(255), @ParentID)
 ENDDECLARE @CategoryID INT
 DECLARE c1 CURSOR FOR SELECT CategoryID FROM Categories WHERE ParentID = @ParentID
 OPEN c1
 FETCH NEXT FROM c1 INTO @CategoryID
 WHILE @@FETCH_STATUS = 0
 BEGIN
  SET @Output = @Output + ', ' + Convert(VARCHAR(255), @CategoryID)
  SET @Output = dbo.GetCategories(@CategoryID, @Output)
  FETCH NEXT FROM c1 INTO @CategoryID
 END
 CLOSE c1
 DEALLOCATE c1RETURN @Output
END

Now i could execute the following query:

SELECT * FROM Articles WHERE CategoryID IN dbo.GetCategories(1, '')

And it would return all the articles where the CategoryID is 1 or the category is a sub of the category specified.

Hope this helps.