Shell script Switch case statements

option1(){

    echo "Option 1 executing "

}

promptInput

echo "User opted for " ${action}

case $action in

  1)

    option1

    ;;

  2)

    echo -n "Selected option 2"

    ;;

  3 | 4)

    echo -n "Selected option 3 or 4"

    ;;

  *)

    echo -n "unknown option selected"

    ;;

esac