Open Location and "user cancel"

Hi folks,

I’m novice in AppleScript and trying to use mount a network volume by using
open locatin “user:password@url”

I would like to get the result of Mac’s connection dialog (if it shown up) and user clicked on cancel button? i know if everything goes through i wouldn’t see the connection dialog(dialog that Mac brings up to get the user/id from user)
but how if the userid/password is wrong the dialog comes up.
Do you have any idea in this case how can i check the result of the dialog once the user clicks on “Cancel” button ?

Thanks,
Nima