User kokos answered the wonderful hidden features of c# question by mentioning the using keyword. Can you elaborate on that? Although i think it would be better to.
Tracking Down a Meme Thief in “It Feels Personal” The New Yorker
Either way, when the using block is exited (either by successful completion or by error) it is closed. Not using by means that the technology used is incidental, and the focus is on the approach being shown to be feasible.