Simple regular expression question: How to find all @username mentions on a page of html?

Question

I'm new to regular expressions in php.

I have a long string of html. I want to find all occurences of:

@any_username_after_an_at_sign

Could somebody help me recover all of the usernames on a page? I think you use preg_match but I don't know the regular expression to use.

Thanks!!

Answer 1

Try this:

@\S+

and use preg_match_all

Answer 2

You could try:

/@\w+/

But this might pick up some false matches, such as parts of email addresses. Can you tell us something about the context?

It might also be relevant to consider using an HTML parser, although without more information it is hard to be sure.

Answer 3

Simple:

preg_match_all('~@(\w+)\b~', '@me @you', $usernames);
print_r($usernames);

Result:

Array (
  [0] => Array(
    [0] => @me
    [1] => @you
  )
  [1] => Array (
    [0] => me
    [1] => you
  )
)

Once you get this, simply match these against your users' DB table to weed out false positives. You might also want to strip_tags() before you do this to avoid getting text from inside attributes.

Answer 4

Given the context of the twitter page, something like this may work.

'@<a class="tweet-url username"[^>]*>([^<]*)</a>'

but a proper parser will always work better than a regex for this type of problem