Regular Expression for extracting POP3 headers

Question

Hi,

I'm trying to work out how to extract POP3 headers using this regex

^(?[a-zA-Z-]+)(?(?=:).+)$

Delivered-To: [email protected]

The group returns the ':' character as well which I want to avoid. I'm busting trying to work this out but can't.

Need collective wisdom :-)

Answer 1

I would go with something like

/^([^:]+):(.*)$/

Then you would have

• $1 - header name
• $2 - value

Answer 2

Hi,

Just so you are aware, this will not handle wrapped headers. In fact, that regex will take a wrapped header, and prepend it to a real header. Especially if the wrapped header doesn't have a ":" in the following lines.

Building upon Sergej Andrejev's Regex, this one will handle not capturing the wrapped lines:

^([^:\s+]+):(.*)$

However, the best thing to do, is to actually read the headers line by line, and parse accordingly. It's a pain (as I've had to do it for production code), but it's the most accurate.

Cheers!

Dave

Answer 3

Sorry, copied the wrong code:

^(\S+):\s((\s\S:))*)

It works with multi lines.