Category: JavaScript Answers

Sometimes, we want to print an object’s keys and values with JavaScript.

In this article, we’ll look at how to print an object’s keys and values with JavaScript.

How to print an object’s keys and values with JavaScript?

To print an object’s keys and values with JavaScript, we can use Object.entries and the for-of loop.

For instance, we write:

const filters = {
  "user": "abc",
  "application": "xyz"
}

for (const [key, val] of Object.entries(filters)) {
  console.log(key, val)
}

We loop through the key-value pairs of filters by convert it to an array of key-value pair arrays with Object.entries.

In the for-of loop, we destructure the key and value from each array entry into key and val and log them.

Therefore, we see:

user abc
application xyz

logged.

Conclusion

To print an object’s keys and values with JavaScript, we can use Object.entries and the for-of loop.

To return an empty promise with JavaScript, we can use an async function or call Promise.resolve.

For instance, we write:

const p1 = async () => {}
const p2 = () => Promise.resolve()

to create 2 functions that returns empty promises.

p1 is an async function, so it’s a function that always returns a promise.

And since it has no return value, it returns an empty promise.

p2 is a regular function that returns an empty promise by calling Promise.resolve with no arguments.

Sometimes, we want to get HTML from the clipboard in JavaScript.

In this article, we’ll look at how to get HTML from the clipboard in JavaScript.

How to get HTML from the clipboard in JavaScript?

To get HTML from the clipboard in JavaScript, we can listen to the paste event.

For instance, we write:

document.addEventListener('paste', (e) => {
  const html = e.clipboardData.getData('text/html');
  console.log(html)
})

to call document.addEventListener with 'paste' and a callback that runs when we paste onto the page.

In the callback, we get the clipboard data with e.clipboardData.getData('text/html').

Now whenever we copy content from browser tabs and paste it onto the page, we should see the HTML code logged.

Conclusion

To get HTML from the clipboard in JavaScript, we can listen to the paste event.

Sometimes, we want to reload an img every element 5 seconds using JavaScript.

In this article, we’ll look at how to reload an img every element 5 seconds using JavaScript.

How to reload an img every element 5 seconds using JavaScript?

To reload an img every element 5 seconds using JavaScript, we can use the setInterval function.

For instance, we write:

<img src='https://picsum.photos/200/300'>

to add an img element.

Then we write:

const img = document.querySelector('img');
setInterval(() => {
  img.src = 'https://picsum.photos/200/300'
}, 5000);

to select the img element with querySelector.

And in the setInterval callback, we set the src property of the image to a URL.

We pass in 5000 milliseconds as the 2nd argument to run the callback every 5 seconds.

Conclusion

To reload an img every element 5 seconds using JavaScript, we can use the setInterval function.

Sometimes, we want to check if x greater than y and less than z with JavaScript.

In this article, we’ll look at how to check if x greater than y and less than z with JavaScript.

How to check if x greater than y and less than z with JavaScript?

To check if x greater than y and less than z with JavaScript, we can use an if statement.

For instance, we write:

const score = 5
if (score > 0 && score < 8) {
  console.log(score);
}

We check if score is bigger than 0 with score > 0.

And we check if score is less than 8 with score < 8.

Since score is 5, we see score logged.

Conclusion

To check if x greater than y and less than z with JavaScript, we can use an if statement.