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JavaScript

Posted by Javier Lim
Javier Lim
476 Points

game.js:2 Uncaught TypeError: Cannot read property 'getContext' of null => why do i get this error

this is the html code:

<!DOCTYPE html> <html> <head> <title>Shooter Game</title> <link rel="stylesheet" type="text/css" href="style.css"> </head> <body> <canvas id="canvas" width="640" height="480"></canvas> <script src="game.js"></script> </body>

And this is the Javascript code: const canvas = document.getElementById("shooter"); const context = canvas.getContext("2d");

2 Answers

Steven Parker
Steven Parker
242,770 Points
Steven Parker
Steven Parker
242,770 Points

You don't have any HTML elements with the ID of "shooter", so the "getElementById" is returning null.

Did you mean to say "canvas" instead? Or give your canvas element an ID of "shooter"?

Javier Lim
Javier Lim
476 Points
Javier Lim
Javier Lim
476 Points

so what is the code?

Steven Parker
Steven Parker
242,770 Points
Steven Parker
Steven Parker
242,770 Points

It depends on which code you want to change: if you change the HTML, give the canvas id="shooter" (instead of id="canvas"). Or you could change the JavaScript and use getElementById("shooter") instead of getElementById("canvas").