Category: JavaScript Answers

Sometimes, we want to override !important style with JavaScript.

In this article, we’ll look at how to override !important style with JavaScript.

How to override !important style with JavaScript?

To override !important style with JavaScript, we can use the setProperty method.

For instance, we write

document.body.style.setProperty('background-color', 'green', 'important');

to call setProperty to change the background color of the body element.

We call it with 'background-color', 'green' and 'important' to make it an !important style.

Conclusion

To override !important style with JavaScript, we can use the setProperty method.

Sometimes, we want to change the location of the current web page using JavaScript.

In this article, we’ll look at how to change the location of the current web page using JavaScript.

How to change the location of the current web page using JavaScript?

To change the location of the current web page using JavaScript, we set window.location.href to the URL we want to go to.

For instance, we write

window.location.href = 'URL';

to set window.location.href to the string with the URL we want to navigate to.

Conclusion

To change the location of the current web page using JavaScript, we set window.location.href to the URL we want to go to.

Sometimes, we want to access local files with JavaScript.

In this article, we’ll look at how to access local files with JavaScript.

How to access local files with JavaScript?

To access local files with JavaScript, we can let users choose local files with a file input.

Then we can read the file when they choose one or more files.

For instance, we write

<input type="file" />

to add a file input.

Then we get the select files with

const inputElement = document.getElementById("input");
const handleFiles = (e) => {
  const fileList = e.target.files;
};

inputElement.addEventListener("change", handleFiles, false);

We select the input with getElementById.

Then we define the handleFiles function to get the selected files from e.target.files.

Next, we call addEventListener with 'change' to listen for file selections and run handleFiles to get the files selected when selection changes.

Conclusion

To access local files with JavaScript, we can let users choose local files with a file input.

Then we can read the file when they choose one or more files.

Sometimes, we want to detect Ctrl+V, Ctrl+C using JavaScript.

In this article, we’ll look at how to detect Ctrl+V, Ctrl+C using JavaScript.

How to detect Ctrl+V, Ctrl+C using JavaScript?

To detect Ctrl+V, Ctrl+C using JavaScript, we can listen to the keyup and keydown events.

For instance, we write

let ctrlActive = false;
let cActive = false;
let vActive = false;

document.body.addEventListener("keyup", (event) => {
  if (event.key == "Control") ctrlActive = false;
  if (event.code == "KeyC") cActive = false;
  if (event.code == "KeyV") vActive = false;
});

document.body.addEventListener("keydown", (event) => {
  if (event.key == "Control") ctrlActive = true;
  if (ctrlActive == true && event.code == "KeyC") {
    event.preventDefault();
    //...
  }

  if (ctrlActive == true && event.code == "KeyV") {
    event.preventDefault();
    //...
  }
});

to call addEventListener to listen for the keyup and keydown events.

Then we check the keys that are pressed with key and code in the keyup event listeners to set a few flags.

In the keydown listener, we check if ctrl is pressed with ctrlActive and check the key pressed with event.code.

If they’re both pressed, then the key combos are pressed.

Conclusion

To detect Ctrl+V, Ctrl+C using JavaScript, we can listen to the keyup and keydown events.

Sometimes, we want to add a duration to a moment object with moment.js and JavaScript.

In this article, we’ll look at how to add a duration to a moment object with moment.js and JavaScript.

How to add a duration to a moment object with moment.js and JavaScript?

To add a duration to a moment object with moment.js and JavaScript, we can use the add method.

For instance, we write

const travelTime = moment().add(2, "hours").format("hh:mm A");

to call add with 2 and 'hours' to add 2 hours to the current date time and return the new date time.

Then we call format to return a time string with the time.

Conclusion

To add a duration to a moment object with moment.js and JavaScript, we can use the add method.