generate registration numbers automatically

[maheen123]

Hi...

Im using three fields in my application.

1)For daily serial....DSerial ,which i want to be generated autoamtically based on date.. forst two digits to show date and other three to show serial number.
2) For Monthy Serial... MSerial , in which first two digits to show current month and other 4 for serial number
3) For Registration Number, RegistrationNo, in which ist two digits for current year in which registered and other 5 for serial


Please help me to do this task. i dont know the steps that i can use to do this for my application to work .

thanks