Validation and custoner detail

[kcount]

Hello all,

 

I'm hoping someone can help with this problem. I have an optometrioc practice where we are selling Contact lenses to our patients on-line.

 

The concern comes in when a customer, or patient in this case, wants to order contacts on an expired prescription..

 

So heres the question:

 

A. How do I add a field to the costomer detail screen for the RX date. (this seems to be the best place for this)

 

B. How do I go about validating this on each order? (prescriptions expire one year from the time they are written)

 

Any help would be appreciated..

 

Kevin