the village buzz

one of the things i end up having to do day in and day out is validating email addresses before shoving them into a database. honestly, i haven’t been doing it as well as i should be. the only real reason i haven’t is that i didn’t have time to sit around with the ruby book and plod through how they do regex. this weekend, i cracked the book and it was simple.

there are a bunch of decent canned javascripts to do just this, but in alot of cases, our email are sent via AJAX, so it would be really handy to do this with ruby and part of a rails controller.

before i got too involved in the whole thing (i did digest the chapter, though) i did a quick google on a regex. i am not at all opposed to borrowing other people’s code.

over at “devx.com”:http://www.devx.com/enterprise/Article/31197/0/page/3 i found this really keen regex:

/\A[\w._%-]+@[\w.-]+.[a-zA-Z]{2,4}\z/

here is my quick and dirty self explanatory test of how it works.

the code:

emails = ["test@example.com","jo@jo.com","rex","f4$m@you.com",
            "test@go,com","test@example.co", "test.example@example.c",
            "testing.example@example.com"]

emails.each do |e|
  if e =~ /\A[\w\._%-]+@[\w\.-]+\.[a-zA-Z]{2,4}\z/
    puts e + ” is a valid email address\n”
  else
    puts e + ” is not a valid address\n”
  end
end

as you would guess, produces output like this:

test@example.com is a valid email address
jo@jo.com is a valid email address
rex is not a valid address
f4$m@you.com is not a valid address
test@go,com is not a valid address
test@example.co is a valid email address
test.example@example.c is not a valid address
testing.example@example.com is a valid email address

let me know if you find anything that makes this regex choke..