Hi, Sorry, I should have said. I usually do say.

C#, 1.1

I will put your code in and let you know.

Thanks for your help.

Best regards,
Dave Colliver.
http://www.LeedsFOCUS.com
~~
http://www.FOCUSPortals.com - Local franchises available

Hi Marc,

(I am writing for ASP.NET)

I have modifed this to use an arraylist as, as you say, List is not part of
.NET 1.1 In the Folder class, all that was in there was setting properties
from a datarow. Nothing special.

With that, I changed object obj to DataRow dr, though that may cause me a
problem. I am not sure yet.

Below is my class. I had to wrap a namespace around the class. I amstill
having a few problems with it. (I really do apologise for not having enough
knowledge in this area to fix it myself. I have spent hours on it now, got
some areas fixed (sort of), but not others. :-(   )

Other things I had to fix due to differences in 1.1  and 2, however, not
sure if I have fixed them correctly.
1. Can't have a static class, so have removed "static".
2. List<> made to an ArrayList. (Mentioned above)
3. in the folders.Add inside the Folders constructor, I have passed a
DataRow. I can't see why this would be any different.
4. folders.TrimToSize() instead of TimeExcess()

If I have made bad assumptions/adjustments, please tell me. All part of the
learning process.

The problem at the moment is in the public static Folder[] GetFolders(). I
was getting cannot implicitly convert object[] to folders.ToArray(), so I
tried a number of things to cast the object, eventually getting (Folder[])
to compile. However, when I run it, I am getting Specified cast is not
valid.

public class Folders
{
 //private static readonly List<Folder> folders;
 private static readonly ArrayList folders;
 private static readonly ReaderWriterLock syncLock = new
ReaderWriterLock();

 static Folders()
 {
  //folders = new List<Folder>();
  folders = new ArrayList();
  //TODO; replace with actual code to initialise from DB

  DataAccessLayer.DataManager DM = new DataAccessLayer.DataManager();
  DataTable DT = DM.FolderList();

  //foreach (object obj in new object[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 })
  foreach (DataRow dr in DT.Rows)
  {
   folders.Add(new Folder(dr));
  }
  //folders.TrimExcess();
  folders.TrimToSize();
 }

 public static Folder[] GetFolders()
 {
  syncLock.AcquireReaderLock(Timeout.Infinite);
  try
  {
   return (Folder[])folders.ToArray();
  }
  finally
  {
   syncLock.ReleaseReaderLock();
  }
 }

 public static void AddFolder(Folder folder)
 {
  syncLock.AcquireWriterLock(Timeout.Infinite);
  try
  {
   folders.Add(folder);
  }
  finally
  {
   syncLock.ReleaseWriterLock();
  }
 }
}

Something else I am looking at, though not sure yet how it will work... is
your AddFolder. The way I think it works is to add a single line. What I
would like to do is to re-run my database query and repopulate the folder
list from scratch. I can probably work this out for myself though. I will
also be wanting to be able to filter the folders based on certain criteria,
such as FolderID = ParentFolderID, again, I should be able to work this out.

Something that I am not sure about though as I can't work it out (though am
partway there) is how to read it the way I have demonstrated with the
Microsoft CMS sample. I am doing it this way...

Folder[] MyFolders = Folders.GetFolders();

  foreach (Folder FD in MyFolders)
  {
   Response.Write(FD.FolderID.ToString());
   Response.Write(FD.FolderName);
  }

Whilst it is not the way I would have liked, I can live with it. If you know
of another way (I know I can change the MyFolders in the foreach to
Folders.GetFolders()) I would appreciate the knowledge.

Something else I am not sure yet (as I can't get it to run properly) is that
because I have removed the static modifier from the class, will that cause
the database to be called each time? This is the main criteria for the
class. The other was to not have to use the "new" when instantiating the
class.

One final question. This is about the difference between 1.1 and 2. The
List<>, what exactly is the difference between List and ArrayList and why
use List over ArrayList?

Thanks for your help.

Best regards,
Dave Colliver.
http://www.ManchesterFOCUS.com
~~
http://www.FOCUSPortals.com - Local franchises available