How can I make a bash script case insensitive?

Question

I'm writing a script that will output something about my friends depending on what name they input, but in the script I put the conditions for the if/then as their names capitalized. Is there a way I can make it so they can put in a lower case letter and it still be the same output?

Answer 1

In bash, you can use the ,, parameter expansion to lowercase a variable value:

#! /bin/bash

read -p Name: name
case ${name,,} in
    (john) echo Hi John! ;;
    (jane) echo Hallo Jane! ;;
    (jack) echo Long time no see, Jack! ;;
    (*)    echo "I don't know you." ;;
esac