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JavaScript Object-Oriented JavaScript: Challenge Making the Game Interactive handleKeydown() Solution

Posted by babyoscar
babyoscar
12,930 Points

Console is throwing error and my console log isn't working

The console says "Uncaught TypeError: Cannot read property 'key' of undefined at Game.handleKeyDown (Game.js:34) at HTMLDocument.<anonymous> (app.js:10)" however many times you press a key, I'm not sure why. Here is my code for the handleKeyDown method:

handleKeyDown (e) {
    if (this.ready) {
        if (e.key === "ArrowLeft") {
            console.log("hello"); //checking if it works, which it doesn't for some reason
        } else if (e.key === "ArrowRight") {

        } else if (e.key === "ArrowDown") {

        }
    }
}

and the keydown event listener in app.js in case you need it:

document.addEventListener('keydown', (event) => {
    game.handleKeyDown();
})

1 Answer

Cameron Childres
Cameron Childres
11,820 Points
Cameron Childres
Cameron Childres
11,820 Points

Hi babyoscar,

In your event listener you have event as a parameter but you aren't passing it to game.handleKeyDown(). When the handleKeyDown() function runs it doesn't have any arguments to work with. Try this out:

document.addEventListener('keydown', (event) => {
    game.handleKeyDown(event);
});
babyoscar
babyoscar
12,930 Points

Thanks! It worked.