“operation successful” message

WordPress makes use of add_settings_error() and related function to setup notifications to display.

Using them is not very straightforward, so easier way might be to make use of hooks like admin_notices or all_admin_notices to output your own message and style it in same way as WP does.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)