ActionScript 2.0 :: [FMX] Getting The First Letters From A String Of Words?

For a rather complex search function I need to get the first letter of each word entered into an input field. At first glance this may not seem like a big problem if every word is neatly seperated by a space. Although people can enter whatever they want into the field I only want to work with the words that start with a-z or A-Z. I'm having a bit of trouble figuring out how I can determine if a character in the string falls into this selection.One of the possibilities is to use charCodeAt(), but that's rather rough. I can walk through the string using indexOf() but I may have trouble finding the next word if characters other than a space come into play. Say I have a string like: Super "big hamburger"notice the 'accidental' double space after super) What I want to get out of it is: Super big Hamburgerhich I later decrease to: s b h