Colelctions SDK: Wrapper for request body

This documentation - RequestBody - Postman Documentation mentions that RequestBody class

provides a nice wrapper for url-encoded, form-data, and raw types of request bodies.

Which methods am i looking at for those wrappers? I could not find the appropriate methods. Lets say I want to know all the request params in an endpoint. It seems that I have no other option than to check the mode and iterate over appropriate object (based on mode) to get those params.