Reversing the effect of this code

[gergy008]

Okay, Earlier on I asked someone if they could show me a shorter way of making letters one higher, Like A becomes B and B becomes C in a string.

 

I was wondering if using this code:

 

for($i=0, $n=strlen($text); $i<$n; ++$i)
{
$val = ord($text[$i]);
if(($val>=65 && $val<=90) || ($val>=97 && $val<=122))
{
	$base = ($val<=90) ? 65 : 97;
	$text[$i] = chr($base + ($val-$base+1)%26);
}
}

 

I could reverse it's effect and make A become Z and B become A in a string.

 

Thanks in advance!

[fortnox007]

I would love to know that too, I can only think of a str_replace() way

[AbraCadaver]

What's wrong with strtoupper() and strtolower()?

[AbraCadaver]

What's wrong with strtoupper() and strtolower()?

Sorry brain-fart, never mind...

 

In general this increments and the next one decrements:

 

$new = chr(ord($letter) + 1);

$new = chr(ord($letter) - 1);

 

You need to decide what happens if you try and decrement an A or increment a Z, etc...