So far, being a total neophyte when it comes to writing JS, I’m pretty impressed with Bard. I can see it becoming a very useful tool for me in learning how JavaScript works (and eventually how to write it.)
Some months ago, I asked a friend here in the forum if he could do me a favor and create a JavaScript that would pause a background video on one of my websites after a person scrolled a specified distance (which he kindly did for me.)
I then decided to give the same task to Bard, and compare the results. Here’s how it went down…
ME: Create a javascript that pauses a video after a user has scrolled down the page 820 pixels
BARD: Sure, here is the JavaScript code to pause a video after a user has scrolled down the page 820 pixels:
window.onscroll = function() {
var scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
$('video').pause();
}
};
BARD: This code will listen for the scroll event on the window object. When the event is fired, it will get the current scroll position of the window using the window.pageYOffset property. If the scroll position is greater than or equal to 820 pixels, the code will pause the video using the $(‘video’).pause() method.
To use this code, you would need to add it to the HTML document where the video is located. For example, you could add it to the head section of the document:
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script>
window.onscroll = function() {
var scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
$('video').pause();
}
};
</script>
</head>
BARD: This code would pause the video when the user has scrolled down the page 820 pixels.
ME: Please change the above code into vanilla javascript
BARD: Sure, here is the vanilla JavaScript code to pause a video after a user has scrolled down the page 820 pixels:
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
for (const video of document.querySelectorAll('video')) {
video.pause();
}
}
});
BARD: This code is similar to the jQuery code, but it uses the native addEventListener() method to listen for the scroll event. It also uses the querySelectorAll() method to get all of the video elements on the page, and then it pauses each one using the pause() method.
To use this code, you would need to add it to the HTML document where the video is located. For example, you could add it to the head section of the document:
<head>
<script>
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
for (const video of document.querySelectorAll('video')) {
video.pause();
}
}
});
</script>
</head>
BARD: This code would pause the video when the user has scrolled down the page 820 pixels.
ME: please adjust to the code to target a video with the ID myVid
BARD: Sure, here is the code to target a video with the ID myVid:
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
}
});
BARD: This code is similar to the previous code, but it uses the getElementById() method to get the video element with the ID myVid. It then pauses the video using the pause() method.
To use this code, you would need to add it to the HTML document where the video is located. For example, you could add it to the head section of the document:
<head>
<script>
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
}
});
</script>
</head>
BARD: This code would pause the video with the ID myVid when the user has scrolled down the page 820 pixels.
ME: Please adjust the code so the video starts playing if the user scrolls back up
BARD: Sure, here is the code to adjust the code so the video starts playing if the user scrolls back up:
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
} else if (scrollTop < 820) {
myVid.play();
}
});
BARD: This code is similar to the previous code, but it also checks if the scroll position is less than 820 pixels. If it is, the code will play the video using the play() method.
To use this code, you would need to add it to the HTML document where the video is located. For example, you could add it to the head section of the document:
<head>
<script>
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
} else if (scrollTop < 820) {
myVid.play();
}
});
</script>
</head>
BARD: This code would pause the video with the ID myVid when the user has scrolled down the page 820 pixels, and it would play the video when the user scrolls back up.
ME: Please add a listener to ensure the DOM content has fully loaded
BARD: Sure, here is the code to add a listener to ensure the DOM content has loaded:
document.addEventListener('DOMContentLoaded', function() {
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
} else if (scrollTop < 820) {
myVid.play();
}
});
});
BARD: This code is similar to the previous code, but it also listens for the DOMContentLoaded event. This event is fired when the DOM content has finished loading. So, by listening for this event, we can ensure that the video will not be paused until the DOM content has finished loading.
To use this code, you would need to add it to the HTML document where the video is located. For example, you could add it to the head section of the document:
<head>
<script>
document.addEventListener('DOMContentLoaded', function() {
const myVid = document.getElementById('myVid');
window.addEventListener('scroll', function() {
const scrollTop = window.pageYOffset;
if (scrollTop >= 820) {
myVid.pause();
} else if (scrollTop < 820) {
myVid.play();
}
});
});
</script>
</head>
BARD: This code would pause the video with the ID myVid when the user has scrolled down the page 820 pixels, and it would play the video when the user scrolls back up. It would also ensure that the video is not paused until the DOM content has finished loading.
ME: How is the script you created different from the following script (this is the script that my friend created for me.)
document.addEventListener(
'DOMContentLoaded',
function () {
'use strict';
const video = document.querySelector('#myVid');
const scrollHandle = () => {
if (window.pageYOffset > 820) video.pause();
else video.play();
};
window.addEventListener('scroll', scrollHandle, false);
},
false
);
BARD: The main difference between the two scripts is that the first script uses the getElementById() method to get the video element with the ID myVid, while the second script uses the querySelector() method to get the first video element on the page. The second script also uses a function expression to create a function that is called when the scroll event is fired. This function checks the scroll position and pauses or plays the video accordingly.
The first script is more explicit, as it uses the getElementById() method to get the video element with the ID myVid. This makes it easier to understand what the code is doing. The second script is more concise, as it uses the querySelector() method to get the first video element on the page. This makes it more efficient, as it does not need to specify the ID of the video element.
Ultimately, the best script to use depends on your specific needs. If you need to be explicit about what the code is doing, then the first script is a good choice. If you need to be efficient, then the second script is a good choice.
So Bard got the job done - albeit in a different way than my friend did. I’ve noticed that Bard usually will write code using jQuery unless you specify beforehand to use vanilla JS.