asp.net-mvc – MVCMailer SendAsync和删除附件

我无法弄清楚如何处理消息以释放附加到消息附件的进程.

按照说明here ….

private IUserMailer userMailer = new UserMailer();

    public IUserMailer UserMailer
    {
        get { return this.userMailer; }
        set { this.userMailer = value; }
    }


      using (SmtpClientWrapper client = new SmtpClientWrapper())
        {
            client.SendCompleted += (sender,e) =>
            {
                if (e.Error != null || e.Cancelled)
                {
                    // Handle Error
                }

                //Use e.UserState

                //?? How can I use the userstate?? There are no
                // instructions??

                // Delete the saved attachments now. 
                // This will not work since the mailmessage process 
                // is still attached.
                Parallel.ForEach(imageList,image =>
                {

                    if (System.IO.File.Exists(image))
                    {
                        System.IO.File.Delete(image);
                    }

                });

            };

            // SendAsync() extension method: using Mvc.Mailer
            // farm is my model imageList is a list of file locations for the 
            // uploaded attachments
          UserMailer.Submission(farm,imageList).SendAsync("user state object",client);
        }