How can I determine the state of an object with a trigger?

By "determine", do you mean use it in a condition of a trigger?

Yes. I want to create an action based on the state of the object.

There is a "when state is" trigger action

But many also add triggers and use conditions to check the state of an object.

https://community.articulate.com/series/articulate-storyline-360/articles/storyline-360-working-with-triggers#conditions

Great! Thank you!