Feed dmenuexit the commands from i3exit.

.local/bin/dmenuexit

@@ -1,6 +1,7 @@
 #!/bin/bash
 
-ACTION="$(xargs -n 1 <<<"Lock Suspend Hibernate Logout Shutdown Reboot" | dmenu -i -p "exitctl")"
+COMMANDS="$(i3exit commands | sed 's/\,/\ /g' | sed 's/.*/\L&/; s/[a-z]*/\u&/g')"
+ACTION="$(xargs -n 1 <<<"$COMMANDS" | dmenu -i -p "exitctl")"
 [ -z "$ACTION" ] && exit 1
 echo "INFO: Selected action $ACTION."
 
@@ -9,26 +10,7 @@ CONFIRMATION="$(xargs -n 1 <<<"No Yes" | dmenu -i -p "Are you sure you want to $
 
 echo "INFO: Action confirmed."
 
-case "${ACTION,,}" in
-lock)
-	loginctl lock-session
-	;;
-suspend)
-	systemctl suspend
-	;;
-hibernate)
-	systemctl hibernate
-	;;
-logout)
-	i3-msg exit
-	;;
-shutdown)
-	poweroff
-	;;
-reboot)
-	reboot
-	;;
-*)
+if ! i3exit "${ACTION,,}"; then
 	echo "ERROR: Invalid action '${ACTION,,}'." 1>&2
-	;;
-esac
+	exit 2
+fi

.local/bin/i3exit

@@ -37,9 +37,16 @@ case "$1" in
     shutdown)
         $logind poweroff
         ;;
+    commands)
+        echo "lock,logout,switch_user,suspend,hibernate,reboot,shutdown"
+        ;;
+    help)
+        cmds="$($0 commands)"
+        echo "Usage: $0 ${cmds//\,/\, }"
+        ;;
     *)
         echo "== ! i3exit: missing or invalid argument ! =="
-        echo "Try again with: lock | logout | switch_user | suspend | hibernate | reboot | shutdown"
+        $0 help
         exit 2
 esac