Question

Take these four formats of the from parameter in an email’s header:

From: Jon Doe <[e-mail]>

From: "Jon Doe" <[e-mail]>

From: <[e-mail]>

From: [e-mail]

Has anybody made a regular expression that can match the email address to use in preg_match for these? I have tried a few but the < and > are catching them out

Answer 1

The regex you are looking for is

^From:.*?<?(\S+@\S+?)>?\s*$  
This will match the whole thing in any of the 4 cases

If you are looking to match just email it has been asked again and again… just search for regex email

Email validation which will include any email with a + sign or . in the email as well as the basics would look like

\b[!#\$%&'\*\+\-/=\?\^_`{\|}~a-zA-Z0-9][!#\$%&'\*\+\-/=\?\^_`{\|}~a-zA-Z0-9\.]*[!#\$%&'\*\+\-/=\?\^_`{\|}~a-zA-Z0-9]@[a-zA-Z0-9\-][a-zA-Z0-9\-\.]+[a-zA-Z0-9\-]\b
This is what I use.