SteamVR Controller Input Syntax

Currently, im working on a game project that requires input from VR Controller. Im following a tutorial video from 2016. Can someone please help me to tell me what the code of the newer vesrion of SteamVR that has the same purpose of this code?
(this code might have some problems, because im retyping it from blurry video)

Code (CSharp):

1. var device = SteamVR_Controller.Input((int)ArrowManager.Instance.trackedObj.Index);
2.         if (joint == null && device.GetTouchDown(SteamVR_Input_ActionFile_DefaultBinding_ControllerTypes.Button???.Trigger)){
3.             }