Compare and find differences in string

First off im sorry for making so many help threads over the past couple of days but im new to autoit and im still figuring it out.

I know there is a stringcompare function that tells if the string is equal larger or smaller.

But what im looking for is a way to also show what text is differant, so if the first string is "12345" and the second was "12354" it would return 54 as being differant and preferable the location of the string.

I assumed a udf would have been available but i couldnt find anything.  Could somebody link me if a udf is available.

Thanks in advanced