Angular 5 global function & variable among selected components?

Hello guys,

I need a global function for two separate components.
I’m loading two angular components using selectors on a main HTML page.
One has function buttons and its function has to affect content in the other component as well.

I realized this can’t be easily done… how do you guys set up shared function & variables between two angular components?
I’m trying to create a single button which can load tab contents in two separate components.
is using angular local storage a solution to store certain function and variables?

Thanks in advance,