I do it simply like this: If an e-mail needs to be sent, the editor sets a checkbox to true, during afterpublish the e-mail gets sent AND the checkbox gets set to false again. This is a save event, not a publish event, therefore you don't get into a loop.

from my experience any property value you set in the AfterPublish Event  will not show in the UI on postback. If you reload from the tree, you will see the change, but you will not see the change on postback, when you click save and publish from the tool bar.

Yep, which is why I save the url in the context items and refresh the page afterwards, so all the way at the end of my eventhandler I do this:

if (((Page)HttpContext.Current.Handler).Items.Contains("RedirectUrl")) {
                ((Page)HttpContext.Current.Handler).Items.Remove("RedirectUrl");
}

((Page)HttpContext.Current.Handler).Items.Add("RedirectUrl", HttpContext.Current.Request.Url.ToString());
((Page)HttpContext.Current.Handler).PreRender += PreRender;

And the in the PreRender handler I refresh the page:

private static void PreRender(object sender, EventArgs e)
{
   if (((Page)HttpContext.Current.Handler).Items.Contains("RedirectUrl") && !string.IsNullOrEmpty((string)((Page)HttpContext.Current.Handler).Items["RedirectUrl"])) {              
   HttpContext.Current.Response.Redirect((string)((Page)HttpContext.Current.Handler).Items["RedirectUrl"]);
   }
}

Yes, this is an awkward little hack, but it has worked very well for me so far. :)

yep, I did an awkward hack too, so you may like it:-)

My requirements are slightly different in that sending an email is the default behaviour

public ApplicationInitializer()
{
    Document.BeforePublish += FlagForNotifications;
    Document.AfterPublish += NotifySubscribers;
}

private static void FlagForNotifications(Document sender, umbraco.cms.businesslogic.PublishEventArgs e)
{
    //Note: this code is probably not suitable for a multi-web-server setup.
    var prop = sender.getProperty("notifacationEmailSent");
    if (prop.Value is int && (int)prop.Value == 1)
        return;

    prop.Value = 1;
    HttpContext.Current.Items["SendNotification"] = true;
}

private static void NotifySubscribers(Document sender, umbraco.cms.businesslogic.PublishEventArgs e)
{
    if (HttpContext.Current.Items["SendNotification"] == null)
        return;

    umbraco.library.UpdateDocumentCache(sender.Id);

    var notifier = new EmailNotifier()
    {
        DocumentTitle = sender.Text,
        DocumentUrl = umbraco.library.NiceUrl(sender.Id),
        CategoryIds = sender.GetPropertyAsNodeCollection("categories").Where(n => n.NodeTypeAlias == "CategoryComponent").Select(n => n.Id).ToArray(),
        BaseUrl = HttpContext.Current.Request.Url.GetLeftPart(UriPartial.Authority),
        MailConfig = HttpContext.Current.Server.MapPath("/Mail.config"),
        HttpContext = HttpContext.Current,
        NodeId = sender.Id
    };

    Log.Add(LogTypes.Publish, sender.Id, string.Format("Starting thread to send email notifications for '{0}'", sender.Text));

    var start = new ThreadStart(notifier.Execute);
    var t = new Thread(start) { Priority = ThreadPriority.Lowest };
    t.Start();
}

For some reason AfterClearDocumentCache wasn't working for me, but this does the trick.

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