how to extend the GUILayout scrollview's function?

I create a Logger view with GUILayout:lable () and GUILayout:BeginScrollView().

Now the ScrollView is build-In support mouse wheel event. How can i extend it to support "home " and "end " keyboard event to scroll to top and bottom.

I know it's can be imp inside the update() .But any other way?

because If I want to achieve when the user press "end" button then It will automatic scroll down to bottom , But when the user drag the scroll bar manually ,It's will restore (not scroll down automaticlly) thanks.

any hint?

Regards!