Question

Like the title suggests I need to do something like so…

$i++;//we all know this.

$value = 'a';

increment($value);// i need this functionality
//output 
string [ b ]

///here are some more samples, to help you understand...

increment('b'); //output// c
increment('z'); //output// A [capital A not fussy but would be good :) ]
increment('9'); //output// a1
increment('a1'); //output// a2
increment('aa1'); //output// aa2

and so on…
UPDATE

well lets say I use numeric values
$id++;
I would end up with a massive number eventuall 1310743942525;
which can take alot more space than say `ab34c9″ im trying to save length of characters to save on db …

Answer 1

You try to treat it as a base 62 number:
http://www.pgregg.com/projects/php/base_conversion/base_conversion.php

with source code at

http://www.pgregg.com/projects/php/base_conversion/base_conversion.inc.phps

convert it to decimal, increment, and convert it back to base 62

UPDATE

From how I read the code, you could have a workflow like this:

$value = 'ab8Zb';
$value_base10 = base_base2dec($value, 62);
$value_base10++;
$value = base_dec2base($value_base10, 62); // should be 'ab8Zc'