true, but regardless of what is used, the upload takes a second or so, so it
may never even be seen by the user.
I have an upload page and I tried adding one to it, but due to the time it
actually took to upload the file the user never saw the progress/animation
on the screen.

re:
!> The server doesn't know what size the file is until it's done uploading

Indeed.

re:
!>  so I think your best option is to either use an animated gif to show
!> "something" while the upload is going on, or use AJAX.

Another option would be to use an animated GIF to keep the user
entertained while the upload finishes and create a FileSystemWatcher
object to redirect the user to "uploadFinished.aspx" when the file has finished uploading.

To do that, you'll have to import the FileSystemWatcher namespace :

System.IO.FileSystemWatcher

Something like this ?

public void CreateWatcher()
{
//Create a new FileSystemWatcher
FileSystemWatcher watcher = newFileSystemWatcher();

//Set the filter to only catch ZIP files.
watcher.Filter = "*.zip";

// Perhaps a variable could be created to hold the exact name
// of the file in the filter, obtained from the File.Upload textbox.

//Subscribe to the Created event.
watcher.Created += new FileSystemEventHandler(watcher_FileCreated);

//Set the monitored path to your upload directory
watcher.Path = @"C:\Temp\";

//Enable the FileSystemWatcher events.
watcher.EnableRaisingEvents = true;
}

void watcher_FileCreated(object sender, FileSystemEventArgs e)
{
//When the .zip file has been created in C:\Temp\ ...
Response.Redirect("~/uploadFinished.aspx", false);
return;
}

I haven't done this...but it seems quite possible.
If you try it, please let us know if it worked.

Juan T. Llibre, asp.net MVP
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