How to combine Regex with removing space and # character

Question

I have this array, that I need to remove white spaces and # hashtag character:

array (size=7)
  0 => string 'darwin' (length=6)
  1 => string ' #nature' (length=8)
  2 => string ' explore' (length=8)
  3 => string ' galapagos' (length=10)
  4 => string 'karma' (length=5)

  foreach ($feedSinglePosts["hashtags_list"] as $key=>&$item) {
     $item = preg_replace('/(\s|^)/', '', $item);
     $item = preg_replace('/\#+/', '', $item);
  }

The Regex above works well but I want to make it one line if possible . When I do: /(\\s|^)\\#+/ it outputs this:

array (size=7)
  0 => string 'darwin' (length=6)
  1 => string 'nature' (length=6)
  2 => string ' explore' (length=8)
  3 => string ' galapagos' (length=10)
  4 => string 'karma' (length=5)

How to make the regex on liner that removes white spaces and3 hashtag.

Answer 1

It appears that the characters will be at the beginning or end. If so then no need for loops or regex:

array_walk($feedSinglePosts["hashtags_list"], function(&$v) { $v = trim($v, "\n\r #"); });

If you need to remove them anywhere:

$feedSinglePosts["hashtags_list"] = str_replace(["\n","\r"," ","#"], "", $feedSinglePosts["hashtags_list"]);

Answer 2

A non-regex way with array_walk() and trim() ,

<?php
    $array = ['darwin' ,' #nature',' explore', ' galapagos','karma'];
    function remove_hash_space(&$value,$key){
         $value = trim($value,'# ');
     }
    array_walk($array, 'remove_hash_space');  
    print_r($array);
   ?>

DEMO: https://3v4l.org/nOadH

OR with single line array_map() ,

 $array = array_map(function($e){return trim($e,'# ');},$array);  

DEMO: https://3v4l.org/OaS1F

Answer 3

You may use

$arr = ['darwin',' #nature',' explore',' galapagos','karma'];
print_r( preg_replace('~^[\s#]+~', '', $arr) );
// => Array ( [0] => darwin [1] => nature [2] => explore [3] => galapagos [4] => karma )

See the regex demo

The ^[\\s#]+ pattern matches 1 or more occurrences ( + ) of whitespace or # characters ( [\\s#] ) at the start of the string ( ^ ).

If your strings may contain some wierd Unicode whitespace, consider adding the u modifier: ~^[\\s#]+~u .

If you only need to handle horizontal whitespace, replace \\s with \\h .