Knight gave Paul Lambert's side the lead in the 24th minute, when the usually efficient Darlington defence failed to deal with a Matt Bloomfield cross from the right, allowing Knight to hold off his marker and pull off an acrobatic right-footed scissor kick, sending the ball into the bottom left corner.
The game was sealed by Scott McGleish with six minutes to play when he charged down Steve Foster as the defender was trying to clear.
The ball bounced off McGleish who won the race and took it past David Stockdale to place the ball into the net, sending Lambert dancing down the touchline with delight.
The first goal seemed to lift the home side and they upped the tempo of play. Knight could have extended the lead soon after as he found himself with the ball in the box, but was thwarted by a covering defender before he could unleash a shot.
By this stage, the Quakers defence were growing frustrated with the constant threat posed by Knight and it eventually got to Ricky Ravenhill, who dived in with his studs up on the frontman to pick up the game's first booking shortly before half-time.
Frank Fielding was largely untroubled by the Darlington attack for the entire first half and it continued to be the case in the second, as most of the action occurred in the visitors' half.
It was Knight again who had the best chance for Wycombe when Craig Woodman played a delightful ball to the striker, who with one touch turned and fired in a looping shot, forcing Stockdale in another great save.
Rob Purdie had arguably Darlington's best chance of the match after 64 minutes, striking the ball from 20 yards out and just missing the angle by inches.