I think what you are asking is to show a message box multiple times without clicking a button for each showing. A possible solution would be to use a timer that is started when you click the button then when the timer elapses, show the message box.
See
http://msdn.microsoft.com/en-us/library/system.timers.timer%28v=vs.71%29.aspx[
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I would caution you though, I do not think that this is really a good idea (showing message boxes automatically) as it tends to anger users when they have to dismiss message boxes continually.