How to change spaces to underscore and make string case insensitive?
use replaceAll and toLowerCase methods like this:
myString = myString.replaceAll(" ", "_").toLowerCase()
This works for me:
itemname = itemname.replaceAll("\\s+", "_").toLowerCase();
replaceAll("\\s+", "_") replaces consecutive whitespaces with a single underscore.
"first topic".replaceAll("\\s+", "_") -> first_topic
"first topic".replaceAll(" ", "_") -> first__topic