Carmelo Anthony has played alongside J.R. Smith long enough now to know these hot streaks can arrive in a hurry, and depart just as quickly.

“That’s what he do,” Anthony said. “That’s J.R. Smith. Some nights he makes those shots. Some nights he don’t.”

Those shots have been falling now for a week, like water into a rain barrel. Smith has come off the bench to take over games, to turn them into his own playthings. He scored 37 points on 12-of-18 shooting on Friday night against the defense-less Bobcats. He is the first player since Ricky Pierce, 23 years ago, to score 30 or more points off the bench in three straight games.

If Smith keeps going like this — and of course there is no guarantee of that — the whole equation changes and the Knicks become a threat this spring to everybody, maybe even the Heat.

The Knicks beat the Bobcats at the Garden, 111-102, which doesn’t mean much. They were playing against Bismack Biyombo and Jannero Pargo, who are nothing at all like Chris Bosh, Dwyane Wade and LeBron James.

They’ve won seven straight, though, and what is happening with Smith may mean a great deal if he consistently becomes the Knicks’ second primary scorer, complementing Anthony in April and May.

Suddenly, Smith is getting points all over the court. He’s scoring inside, keeping defenders honest with his drives and giving himself some space to drain the long jumpers on the perimeter. He’s drawing fouls, making his free throws. It’s all working out for him, and Smith says he can hardly remember when he felt this good, this confident.