Im currently developing an app that can parse dates from an email - i.e extract the time and dates from an email (similar to gmail).
Currently I do this in php but this is a tad clunky.
Whats the best language to do this in and are there any existing open source solutions?
I think PHP is as capable as any other language. Can we see the code you're using so we can suggest improvements? I'd use a regular expression... you just need a good one that supports a variety of formats.
What I do in my email client is extract all the tokens delimited by whitespace and then iterate over them using heuristics to decide how to classify each token. For instance if the token has a ':' character in it then I treat it as a time, to be parsed as ##:##:##. If it has '.' or '-' treat it as a day/month/year combo, and you have to decide which end is which... could be any number of combinations. If the token starts with a letter (i.e. isalpha(*string)) then you do a month name lookup. If it's a number it could be the day or year... decide based on length and whether you have an existing day or year already etc. If the token starts with '-' or '+' then it's a timezone, parse accordingly.
Seems to work in the field quite well, my email client has been around for 10 years or so. My code is C++, but you can write the same in PHP easily, it's not particularly language specific.
if you mean the date it was sent (or received), you are retrieving them from the mail headers (for example 'Date:' header) and they have a standard date format, see the RFC 2822
Anyway, if you use javamail (it's open source now) you can get the sent date with
Date sentDate = mail.getSentDate();