Reverse a number inside a string in PHP [closed] - php

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I have a UTF8 string that contains letters and digits. For example:
"Hello World 37. What? 24 last 6650"
and I want to reverse only the digits but keep the numbers in the same place.
The output should be:
"Hello World 73. What? 42 last 0566"

Answer 1

echo preg_replace_callback('/\d+/', function (array $m) { return strrev($m[0]); }, $string);

Answer 2

Before I posted the question, I thought about it and got an idea that works for me, so I'm only posting this question to enrich the database.
function reverseNumbersInString($str){
$tokens = explode(" ", $str);
$res = "";
for ($i = 0; $i < sizeof($tokens); $i++){
if (intval($tokens[$i] > 0 )){
$tokens[$i] = strrev($tokens[$i]);
}
$res .= " " . $tokens[$i];
}
return $res;
}

Answer 3

Maybe something like this:
$string = "Hello World 37. What? 24 last 6650";
preg_match_all('/\d+/', $string, $matches, PREG_OFFSET_CAPTURE);
foreach ($matches[0] as $numberData) {
$numberArray = str_split($numberData[0]);
$reversedNumber = implode('', array_reverse($numberArray));
$string = substr_replace($string, $reversedNumber, $numberData[1], strlen($numberData[0]));
}

Answer 4

This should do it:
$stringWithReversedNumbers = preg_replace_callback(
'/\d+/',
function ($matches) {
return strrev($matches[0]);
},
$originalString
);
Alternatively, if you ONLY want to operate on numbers that are distinct words (i.e. not part of another word, as in if you want hello123goodbye to remain unmodified because the 123 isn't a word by itself), change \d+ to \b\d+\b