I need to extract all whitespace separated "words" at the end of string that either start with the @ character or that consist solely of digits.
For example, I have this string:
hello @tag1 111 world @tag2 @tag3 222 333
I need to obtain
@tag2 @tag3 222 333
I have used this code below:
preg_match_all('~\B@\S+|\b\d+\b~', $string, $match);
With this, I'll get all strings that started with '@' character and numbers, even @tag1 and 111.
I also tried the code below:
$str = 'hello @tag1 111 world @tag2 @tag3 222 333';
$exp = explode(' ', $str);
$arraysfordelete = [];
foreach ($exp as $num => $user) {
if (!preg_match('~\B@\S+|\b\d+\b~', $user, $match)) {
array_push($arraysfordelete, $num);
}
}
$array = array_slice($exp, end($arraysfordelete) + 1);
echo implode(' ', $array);
Any suggestions?
Here is the PHP solution you need:
$str = 'hello @tag1 111 world @tag2 @tag3 222 333';
if (preg_match('~(?<!\S)(@\S+|\d+)(?:\s+(?1))*(?=\s*$)~', $str, $m)) {
echo $m[0];
}
// => @tag2 @tag3 222 333
See the regex demo. Details:
(?<!\S) - a location that is either right after a whitespace or start of string(@\S+|\d+) - Group 1: @ and one or more non-whitespace chars or one or more digits(?:\s+(?1))* - zero or more occurrences of one or more whitespaces and then Group 1 pattern(?=\s*$) - immediately to the right, there must be zero or more whitespaces and end of string.You could use, for example
~[@\d]\S+~
which means match a @ or a digit, followed by one or more non-space characters \S+.
Or
~(?<!\S)[@\d]\S+~
if you want to make sure there is no non-space character preceding the @ or digit.