Sorting...

I have an array filled with CSV data... array ( 20040310, Title, Author 20041115, Title, Author 20040513, Title, Author ) where each array element is 1 line from the csv. When I go to print it out, Im going to explode each by , and then print it out the way I like. BUT, I want to sort them all by those first 8 digits, which happen to be the date. Any way to sort an array by the first x characters in its string? This would save a lot on processor time, otherwise Im going to have to pull an array of those characters, sort it, and then run some matching scheme against the CSV data to print it in the order I like - which would be HUGELY processor intensive. Thanks, Russ