In a bash script, how do I sanitize user input?

Question

I\'m looking for the best way to take a simple input:

echo -n \"Enter a string here: \"
read -e STRING

and clean it up by removing non-alph

Answer 1

Quick and dirty:

STRING=`echo 'dit /ZOU/ een test123' | perl -pe's/ //g;tr/[A-Z]/[a-z]/;s/[^a-zA-Z0-9]//g'`