angularjs - Running $apply on $rootScope vs any other scope

Question

The $apply function can run on any scope, including $rootScope.

Are there cases when it makes a difference if I run it on my local scope or if I run it on my $rootScope?

I'm asking because I'd like to create a helper function that wraps a given function in an $apply. To do that I'd always need to pass in a scope, which is A) annoying and B) not easy because I don't necessarily have a local scope.

I'd like to always have my helper function call $apply on the $rootScope, but not if there's some risk in doing that.

question from:https://stackoverflow.com/questions/17868889/running-apply-on-rootscope-vs-any-other-scope

Answer 1

Running $apply on any scope always results in a $rootscope.$digest. The only case where it might make a difference is when you provide an expression as an argument to $apply. The expression will be evaluated in the current scope (vs. $rootScope), but afterwards $rootscope.$digest is always called.

The source code is quite clear: rootScope.js

Bottom line: If you call $apply with no arguments, it makes no difference.