Swap every two digits

Question

How can I with PHP swap every two digits in a long number value? You can see an example below:

Example: 12345678

Converted to: 21436587

Answer 1

First you have to convert to array.For that use

$array=explode("",$string);

You will get {"1","2","3","4","5","6","7","8"}

Then call the below function.

function swapNumbers($array){
$finalString="";
for($i=0;$i<sizeOf($array);$i++){
if($i!=0){
if($i%2==0){
$finalString.=$array[$i-1].$array[$i];
}
}
if($i==sizeOf($array)-1 && $i%2==1){
$finalString.=$array[$i];
}
}
return $finalString;
}

You will get 21436587.