regex for extracting hash tags without spaces

Question

I'm using this: ``` $t = "#hashtag #goodhash_tag united states #l33t this"; $queryVariable = ""; if(preg_match_all('/(^|\s)(#\w+)/', $t, $arrHashTags) > 0){ array_filter($arrHashTags); array_unique($arrHashTags); $count = count($arrHashTags[2]); if($count > 1){ $counter = 1; foreach ($arrHashTags[2] as $strHashTag) { if (preg_match('/#\d*[a-z_]+/i', $strHashTag)) { if($counter == $count){ $queryVariable .= $strHashTag; } else{ $queryVariable .= $strHashTag." and "; } $newTest = str_replace($arrHashTags[2],"", $t); } $counter = $counter + 1; } } } echo $queryVariable."
"; // this is list of tags echo $newTest; // this is the remaining text ``` The output based on the `$t` above is: ``` #hashtag and #goodhash_tag and #l33t united states this ``` First problem: if `$t = '#hashtag#goodhash_tag united states #l33t this';` i.e without space between two tags, the output becomes: ``` #hashtag and #l33t #goodhash_tag united states this ``` Second problem: if `$t = '#hashtag #goodhash_tag un…

Accepted Answer

Instead of using so many comparisions etc. for your regex. You can simply have the following:

```
$t = "#hashtag #goodhash_tag united states #l33t this #123#tte#anothertag sth";
$queryVariable = "";
preg_match_all('/(#[A-z_]\w+)/', $t, $arrHashTags);
print_r( $arrHashTags[1] );
```

To get them as string with `and` joining them, you can use implode.

```
$queryVariable = implode( $arrHashTags[1], " and " );
```

For the remaining text, you can have `preg_replace` or `str_replace`(whichever you are comfortable with).

Here is the codepad link.

regex for extracting hash tags without spaces

Solution

Problem