sending auto generated mail from register form

[shehnaz20]

please send me the code to generate an auto mail once the user clicks on the register button
my register fields are first name,last name,date of birth,emailid
i need the code to generate the password from the form information and send password and username to this emailid provided by the user....
the password generated should be valid for 3 days so once the user clicks on the link in the email he should be asked to change the password just lik how daniweb does please help me to do this using php
please send the code

[patk570]

No one is going to write code for you. What have you tried so far?

...need a db as well