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KeyCode error?


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I got a code to work, but in the console it's giving me a Uncaught Error: Cannot read property 'Keycode' of undefined. Here's the code.

<!DOCTYPE html><!-- saved from url=(0055)http://www.homeandlearn.co.uk/JS/move_box_keyboard.html --><html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">		<title>The Canvas Tag</title>	</head>	<body>	<header>		<p>Press TAB to begin, W, A, S, D keys to move</p>	</header>		<canvas width="150" height="400" id="canvas_1" tabindex="0">			Canvas tag not supported		</canvas>	</section>	<script>		var canvas = document.getElementById("canvas_1");		canvas.addEventListener('keyup', Update, true);		canvas_context = canvas.getContext("2d");				var x = 0;		var y = 0;		function Game(){			Draw();			Update();		}		function Draw(){			clearCanvas();			canvas_context.fillRect(x, y, 50, 50);		}		function Update(e){			//====================			//	THE W KEY			//====================			if (e.keyCode == 87) {				y = y - 50;			}			//====================			//	THE S KEY			//====================			if (e.keyCode == 83) {				y = y + 50;			}			//====================			//	THE A KEY			//====================			if (e.keyCode == 65) {				x = x - 50;			}			//====================			//	THE D KEY			//====================			if (e.keyCode == 68) {				x = x + 50;			}		}		function clearCanvas() {			canvas.width = canvas.width;		}		setInterval(Game, 1);	</script>	</body></html>
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Simply remove the "Update"-Call from the "Game"-function. if you call the update-function inside the game-function the parameter e is undefined inside the update-function.


You already added an event-listener to call the update-function when the event keyup is fired

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