How to check for a duplicate email address in PHP, considering Gmail (user.name+label@gmail.com)

Question

How can I check for duplicate email addresses in PHP, with the possibility of Gmail\'s automated labeler and punctuation in mind?

For example, I wan

Answer 1

Strip the address to the basic form before comparing. Make a function normalise() that will strip the label, then remove all dots. Then you can compare the addresses via:

normalise(address1) == normalise(address2)

If you have to do it very often, save the addresses in the normalised form too, so you don't have to convert them back too often.