Category: JavaScript Answers

Sometimes, we want to use setTimeout on promise chain with JavaScript.

In this article, we’ll look at how to use setTimeout on promise chain with JavaScript.

How to use setTimeout on promise chain with JavaScript?

To use setTimeout on promise chain with JavaScript, we can create a promise that calls setTimeout.

For instance, we write

await new Promise((resolve) => setTimeout(resolve, 1000));

to create a promise with the Promise constructor by calling it with a callback that calls setTimeout.

And then we use resolve as the callback for setTimeout.

Then we use await to wait for the promise to resolve before running the next line of code.

Conclusion

To use setTimeout on promise chain with JavaScript, we can create a promise that calls setTimeout.

Sometimes, we want to select all div text with single mouse click with JavaScript.

In this article, we’ll look at how to select all div text with single mouse click with JavaScript.

How to select all div text with single mouse click with JavaScript?

To select all div text with single mouse click with JavaScript, we can use the window.getSelection and selectAllChildren methods.

For instance, we write

window.getSelection().selectAllChildren(document.getElementById(id));

to call getElementById to get an element with the given id.

Then we call getSelection to return an object with the selectAllChildren method to get all child nodes from the element with the given id.

Conclusion

To select all div text with single mouse click with JavaScript, we can use the window.getSelection and selectAllChildren methods.

Sometimes, we want to export arrow functions in JavaScript.

In this article, we’ll look at how to export arrow functions in JavaScript.

How to export arrow functions in JavaScript?

To export arrow functions in JavaScript, we can use export directly with arrow functions.

For instance, we write

const hello = () => console.log("hello");
export default hello;

to export the hello function as a default export with export default.

We can also write

export const hello = () => console.log("hello");

to export hello as a named export.

Conclusion

To export arrow functions in JavaScript, we can use export directly with arrow functions.

Sometimes, we want to add delay between actions in JavaScript.

In this article, we’ll look at how to add delay between actions in JavaScript.

How to add delay between actions in JavaScript?

To add delay between actions in JavaScript, we can create a function that returns a promise that delays the script by the time we want.

For instance, we write

const sleep = (ms) => {
  return new Promise((res) => setTimeout(res, ms));
};

const myAsyncFunc = async () => {
  console.log("Sleeping");
  await sleep(3000);
  console.log("Done");
};

myAsyncFunc();

to create the sleep function that returns a promise that calls setTimeout to call res in ms milliseconds.

Then we use await sleep in myAsyncFunc to delay the execution of the function by 3000 milliseconds.

Conclusion

To add delay between actions in JavaScript, we can create a function that returns a promise that delays the script by the time we want.

Sometimes, we want to prevent a webpage from navigating away using JavaScript.

In this article, we’ll look at how to prevent a webpage from navigating away using JavaScript.

How to prevent a webpage from navigating away using JavaScript?

To prevent a webpage from navigating away using JavaScript, we can set the window.onbeforeunload property to a function that returns any value.

For instance, we write

window.onbeforeunload = () => {
  return "";
};

to set window.onbeforeunload to a function that returns an empty string to interrupt navigation with an alert box when we try to navigate to a different page.

Conclusion

To prevent a webpage from navigating away using JavaScript, we can set the window.onbeforeunload property to a function that returns any value.