Calling the SendEmail Event\Logic

Question

Im busy developing a system that registers new users onto the system(registration details sent to the sql database.  In my applicaton, i also have got a logic that sends email to the users.  In other words when a new user has finished the registration process,he or she must receive an email confirming his/her registration onto the system. 

My problem is how do i call the SendEmali event/logic in my Register button so that when i click  on the register event, an email can also be sent to that particular user.  I have separately tested the send mail event and it works,

Urgent

Your assistance will be very much appreciated by me
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