c# - how to implement while loop for processing when clicking -

I hope you can help me with this problem. When I click on an email button, before successfully sending it, it takes a few seconds to process. I need to insert the process image but how to implement it with the "while" loop for processing.
Here is the code: I think I should apply with the customer. Send (msg); for processing. how does it work? I appreciate your example code thanks! (I am using C # and WPF)

  Private Zero BtnSendEmailClick (Object Sender, RoutedEventArgs e) {SmtpClient Client = Zero; Mail message msg = null; {Msg = new mailmessage {{try new mailorder ("me@hotmail.com", "Me Hotmail")}; Msg.To.Add (txtEmailAddress.Text); message. Priority = Mail Preference High; Msg.subject = "Blow Blah"; Msg.Body = "& lt ;; DOCTYPE html> gt; html lang = 'n' xmlns = 'http: //www.w3.org/1999/xhtml'>" + "& Lt; head> gt; & lt; / head & gt;" + "& Lt; body & gt;" + "& Lt; h3> messages & lt; / h3 & gt;" + "& Lt; p & gt;" + LblEmailMessage.Content + "& lt; / p & gt;" + "& Lt; / body & gt;" + "& Lt; / html & gt;"; Msg.IsBodyHtml = True; Client = New SmtpClient {host = "smtp.live.com", port = 25, EnableSsl = true, UseDefaultCredentials = false, credentials = new network credentials ("me@hotmail.com", "password"), DeliveryMethod = SmtpDeliveryMethod. Network}; // How to implement when looping for the processing client Send (msg); LblMessage.Content = "Your mail has been successfully sent!"; } Hold (Exception pre) {lblMessage.Content = ex.Message; }}    
 
 
 You will need to return immediately, and  BackgroundWorker  Once it's finished to send an email, you can use the  Dispatcher  to notify the GUI. For more information, see.  
 Also see.