Is there a code sample for a custom action that can accept parameters?

I looked through the help documentation and couldn't find any reference/example to define a custom action that accepts parameters.

I want to create a custom action FooBar(), which can accept parameters such as ID, Type

I would assume that when I call the action it would be CustomBO.FooBar(12, "AB");

The custom action definition would then use 12 and "AB" parameters as variables in the custom action script.

There are no examples of calling an action with parameters and defining an action with parameters , so does this mean this is not possible or it is, but not documented?