Increment an index that uses numbers and characters
<p>I have a string based code that can be either two or three characters in length and I am looking for some help in creating a function that will increment it.</p>

<p>Each 'digit' of the code has a value of 0 to 9 and A to Z.</p>

<p>some examples:</p>

<p>the first code in the sequence is 000 </p>

<p>009 - next code is - 00A<br>
00D - next code is - 00E<br>
AAZ - next code is - AB0 </p>

<p>the last code is ZZZ.</p>

<p>Hope this makes some sense.</p>
