Question

How to swap pairs of characters in a string with PHP

Answer 1

function SwapPairs($str) {
    if ($str == NULL || empty($str)) {
        return $str;
    }
        
    $arr = str_split($str);
    
    for ($i = 0; $i < count($arr) - 1; $i += 2) {
        $tmp = $arr[$i];
        $arr[$i] = $arr[$i + 1];
        $arr[$i + 1] = $tmp;
    }
    
    return implode("",$arr);
}
        
$str = "aBcDeFgHiJkL";

echo SwapPairs($str);




/*
run:

BaDcFeHgJiLk

*/

 

70+ SQL courses for beginners and professionals