Author: John Au-Yeung

Sometimes, we want to set just the date, ignoring time with JavaScript Date.

In this article, we’ll look at how to set just the date, ignoring time with JavaScript Date.

How to set just the date, ignoring time with JavaScript Date?

To set just the date, ignoring time with JavaScript Date, we pass in a date string into the Date constructor.

For instance, we write

const newDate = new Date(oldDate.toDateString());

to get the oldDate‘s date as a string with toDateString.

Then we pass that into the Date constructor to create a new date object with the date.

Conclusion

To set just the date, ignoring time with JavaScript Date, we pass in a date string into the Date constructor.

Sometimes, we want to check whether a button is clicked by using JavaScript.

In this article, we’ll look at how to check whether a button is clicked by using JavaScript.

How to check whether a button is clicked by using JavaScript?

To check whether a button is clicked by using JavaScript, we add a click listener to the button.

For instance, we write

document.getElementById("button").onclick = () => {
  console.log("button was clicked");
};

to select the button with getElementById.

Then we set its onclick property to a function that’s called when the button is clicked.

Conclusion

To check whether a button is clicked by using JavaScript, we add a click listener to the button.

Sometimes, we want to add 3 days in milliseconds to current Date with JavaScript.

In this article, we’ll look at how to add 3 days in milliseconds to current Date with JavaScript.

How to add 3 days in milliseconds to current Date with JavaScript?

To add 3 days in milliseconds to current Date with JavaScript, we pass in the timestamp for 3 days after today into the Date constructor.

For instance, we write

const dateObj = new Date(Date.now() + 86400000 * 3);

to call Date.now to get the timestamp of the current date time.

Then we add 3 days, which is 86400000 * 3 ms to it.

And we use the sum as the argument of the Date constructor to return a Date object with the date 3 days from now.

Conclusion

To add 3 days in milliseconds to current Date with JavaScript, we pass in the timestamp for 3 days after today into the Date constructor.

Sometimes, we want to fix Bootstrap 4 dropdown menu not working with JavaScript.

In this article, we’ll look at how to fix Bootstrap 4 dropdown menu not working with JavaScript.

How to fix Bootstrap 4 dropdown menu not working with JavaScript?

To fix Bootstrap 4 dropdown menu not working with JavaScript, we should make sure all the required libraries are added.

For instance, we write

<script
  src="https://code.jquery.com/jquery-3.2.1.slim.min.js"
  integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
  crossorigin="anonymous"
></script>
<script
  src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"
  integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
  crossorigin="anonymous"
></script>
<script
  src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"
  integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
  crossorigin="anonymous"
></script>

to add jQuery and popper.js before adding the Bootstrap JavaScript library.

Conclusion

To fix Bootstrap 4 dropdown menu not working with JavaScript, we should make sure all the required libraries are added.