How to find specific number in a string php? - php

Question

I have different strings in which I want to find specific number. If the number is within the string it should print that number.
Strings are like these:
string(9) "path_12.0"
string(9) "path_12.1"
string(9) "path_13.0"
string(9) "path_13.1"
string(9) "path_13.2"
Numbers are like:
int(12)
int(12)
int(13)
int(13)
int(13)
What I tried is:
if (strpos(','.$mainString.',' , ','.$QuestionId.',') != FALSE) {
echo $QuestionId;
} // this doesn't print anything in the body
I also tried the below trick but it also doesn't print anything
if(in_array($QuestionId, explode(',', $mainString))) {
echo $QuestionId;
}
I want to check something like this:
if($questionId is in $mainString) {
echo $questionId;
}
Note: I searched similar questions on StackOverflow but I didn't found a solution which solved my issue, therefore I'm posting this question.

Answer 1

Another option could be to create an array with your strings and use preg_grep with a pattern that checks if the first part of the decimal is equal of one of the numbers.
Example of a pattern where the digits from the array are used as an alternation:
_\K(?:12|13)(?=\.\d+)
_\K Match underscore and forget what was matched
(?: Non capturing group
12|13 Match either 12 or 13
) Close non capturing group
(?=\.\d+) Positive lookahead, assert what is directly on the right is a dot and 1+ digits
For example:
$numbers = [12, 13];
$strings = [
"path_12.0",
"path_12.1",
"path_13.0",
"path_13.1",
"path_13.2",
"path_14.1"
];
$pattern = "/_\K(?:" . implode('|', $numbers) . ")(?=\.\d+)/";
$resullt = preg_grep($pattern, $strings);
print_r($resullt);
Result
Array
(
[0] => path_12.0
[1] => path_12.1
[2] => path_13.0
[3] => path_13.1
[4] => path_13.2
)
Php demo
Or if you want to print the numbers only, you might use array_reduce and collect the matches:
$result = array_reduce($strings, function($carry, $item) use ($pattern){
if (preg_match($pattern, $item, $matches)){
$carry[] = $matches[0];
}
return $carry;
});
print_r($result);
Result
Array
(
[0] => 12
[1] => 12
[2] => 13
[3] => 13
[4] => 13
)
Php demo

Answer 2

You can use below snippet,
$paths = ["path_12.0", "path_12.1", "path_13.0", "path_13.1", "path_13.2", ];
$nos = [12, 12, 13, 13, 13, ];
function strpos_arr($needle,$haystack)
{
if (!is_array($haystack)) {
$haystack = [$haystack];
}
foreach ($haystack as $what) {
if (($pos = strpos($what,(string)$needle)) !== false) {
return $pos;
}
}
return false;
}
foreach ($nos as $key => $value) {
// checking if question id in in path array with str pos
if(strpos_arr($value,$paths) !== false){
echo $value."\n";
}
}
Demo.

Answer 3

$array_strings = ["path_12.0", "path_12.1", "path_13.0", "path_13.1", "path_13.2"];
$array_numbers = [12, 22, 13, 11, 17];
$results = [];
foreach ($array_strings as $string){
preg_match_all('!\d+\.*\d*!', $string, $matches);
foreach ($array_numbers as $number){
if (in_array($number, $matches[0])){
array_push($results, $number);
}
}
}
print_r($results);
results: Array ( [0] => 12 [1] => 13 )
Note 1: array answers can have duplicate values.