I don't think the idea of handling form text value differently if it looks like an email addess is particularly wise, but if the OP is determined to go with such an approach, then my regex above is as good a heurstic as anything else. Sure, you could use a CPAN module that can correctly parse RFC822 addresses, but since we are dealing with a web form where users have typed in stuff by hand, its fairly unlikely they're typing the full RFCish stuff involving quoting, <> etc.

In reply to Re: special handling with regular expressions by dave_the_m
in thread special handling with regular expressions by data67

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