Question

I’m having to pass 3 variables (int) within a single numeric string called $id. To do this I’m creating $id using padding which I can then explode to get the variables. It has to be numeric otherwise I’d use underscores between the variables. I’m using eleven zeros as padding as I know the variables won’t have that many zeros. So currently if I have:

$int_one = 1;
$int_two = 2;
$int_three = 3;

That would be:

$id = "1000000000002000000000003";

To create the new Id I use:

$id = $int_one . "00000000000" . $int_two . "00000000000" . $int_three;

And to separate the Id I use:

$int_one = 0;
$int_two = 0;
$int_three = 0;
if (strpos($id,"00000000000") !== false) {
    $id = strrev($id); // Reversed so 0's in int's don't get counted
    $id = explode("00000000000", $id);
    // Set numbers back the right way
    $int_one = strrev($id[2]);
    $int_two = strrev($id[1]);
    $int_three = strrev($id[0]);
}

This runs into problems when an individual variables is 0. Is there a way to overcome this or does it need a major rethink?

EDIT: $id is supposed to be a numeric string not int

Needs to handle int variables between 0 – 2147483647

Answer 1

You can just use some string magic to assure that no number has more than one zero in a row, and delimit the values using ’00’. This generates a numeric string that can be uniquely decoded no matter the size or composition of the ints.

$a = 100;
$b = 0;
$c = 120;

// Encode;

$id = str_replace('0', '01', $a).'00'
     .str_replace('0', '01', $b).'00'
     .str_replace('0', '01', $c);

// $id = "101010001001201"

// Decode;

$tmp = split('00', $id);
$a2 = intval(str_replace('01', '0', $tmp[0]));
$b2 = intval(str_replace('01', '0', $tmp[1]));
$c2 = intval(str_replace('01', '0', $tmp[2]));

// $a2 = 100, $b2 = 0, $c2 = 120