javascript - onbeforeunload custom dialog message not working -

i have scenario need show dialog box asking user recheck changes have made

so doing onbeforeunload , want message saying "please recheck rating , feedback have provided"

$window.onbeforeunload = function() {         var dialogtext = 'please recheck rating , feedback have provided';         return dialogtext;     }; 

but end showing "changes made may not saved"(default message).

i dont understand why getting such

any appreciated.

have tried:

$scope.$on('$destroy', function(e){   // show message });