Regex

http://rubular.com/ tool which helped me :-)

https://regex101.com this is really good online regex page

Some nice regex to extract info

• Recursive Regex to grab nested curly brackets parent stuff i.e. text -> test {{test {test}} test test {test{test}}} results -> {{test {test}} test test {test{test}}}

/\{ (?: [^{}]+ | (?R) )*+ \}/xmig

or

/(?=\{)(?=((?:(?=.*?\{(?!.*?\2)(.*\}(?!.*\3).*))(?=.*?\}(?!.*?\3)(.*)).)+?.*?(?=\2)[^{]*(?=\3$)))/xmig

• Extract data from HTML list li elements

/<li>(.*?)<\/li>/i

• Get full json bit with "patern" interpolation i.e. {"patern": "test"}

/{"patern":.*?"(.*?)"}/i

• Extracting data from RRS feed (link path, images ...)

  preg_match_all('#<\s*img [^\>]*src\s*=\s*(["\'])((.*?))\1#im', $text, $fromimg);
  $text = preg_replace('/<\s*img[^>]+>/Ui', '', $text);


  /* --- replace a tag which link to image --- */
  preg_match_all('/<a.*href="([^<].*(png|jpg|gif|jpeg))"[^>]*>(.*?)<\/a>/im', $text, $fromlinks);

  for ($i = 0; $i < sizeof($fromlinks[2]); $i++) {
    $mid_text = $fromlinks[2][$i]; // this is the text or other in the middle of link which link to image
    $text_tmp = preg_replace('/<a.*href="([^<]*[\.png|\.jpg|\.jpeg|\.gif]+)"[^>]*>(.*?)<\/a>/im', $mid_text, $text, 1);
    $text = $text_tmp;
  }
  /* --- remove text below image span color #696969 -- */


  $text = preg_replace('/<span.*style="([^<]*696969+)"[^>]*>(.*?)<\/span>/im', "", $text);

• a => b, a => or a=> or b=>k string checker with case insensitive

/(^[a-z]{1}\s?)(=>)(\s?[a-z]{1}?)/i

fixed second part empty or letter only (with or without space)

/(^[a-z]{1}\s{1}?)(=>)(|(\s{1}?[a-z]{1}?))$/i

Youtube and Vimeo

/(https?:\/\/)?(www.)?(youtube\.com\/watch\?v=|youtu\.be\/|youtube\.com\/watch\?feature=player_embedded&v=)([A-Za-z0-9_-]*)(\&\S+)?(\?\S+)?/

/https?:\/\/(www.)?vimeo\.com\/([A-Za-z0-9._%-]*)((\?|#)\S+)?/

Email validation

/\A([^@\s]+)@((?:[-a-z0-9]+\.)+[a-z]{2,})\z/i/

URL

if you would like to confirm that url pattern is expected and grab last bit after placeholder i.e. url to match and result is 'https://buy.com/app/prefix/order/53534534" and want to get "order/53534534"

\^https?:\/\/(www\.)?buy.com\/app\/prefix\/([^&]*)\gm