(defun gsetting-key-replace ()
  "convert gsetting key name from _ to -"
  (interactive)
  (setq case-fold-search nil)

  (save-restriction
  (narrow-to-region (region-beginning) (region-end))

  (goto-char (point-min))
  (while (search-forward "_" nil t)
    (replace-match "-"))

  ;; repeat for other string pairs
  )
)