Author: John Au-Yeung

Sometimes, we want to set a JavaScript onclick event to a class with CSS.

In this article, we’ll look at how to set a JavaScript onclick event to a class with CSS.

How to set a JavaScript onclick event to a class with CSS?

To set a JavaScript onclick event to a class with CSS, we loop through each element and set its onclick property to the click handler.

For instance, we write

const elements = document.getElementsByClassName("someClassName");

for (const element of elements) {
  element.onclick = () => {
    console.log("Clicked in an element of the class.");
  };
}

to select all elements with class someClassName with getElementsByClassName.

Then we loop through each element with a for-of loop and set their onclick property to their click handler functions.

Conclusion

To set a JavaScript onclick event to a class with CSS, we loop through each element and set its onclick property to the click handler.

Sometimes, we want to add another class to a div with JavaScript.

In this article, we’ll look at how to add another class to a div with JavaScript.

How to add another class to a div with JavaScript?

To add another class to a div with JavaScript, we call classList.add.

For instance, we write

document.getElementById("hello").classList.add("someClass");

to select the element with getElementById.

Then we call its classList.add method to add the someClass class to it.

Conclusion

To add another class to a div with JavaScript, we call classList.add.

Sometimes, we want to convert seconds to a date object with JavaScript.

In this article, we’ll look at how to convert seconds to a date object with JavaScript.

How to convert seconds to a date object with JavaScript?

To convert seconds to a date object with JavaScript, we create a date with timestamp 0 and add the seconds we want to it.

For instance, we write

const toDateTime = (secs) => {
  const t = new Date(1970, 0, 1);
  t.setSeconds(secs);
  return t;
};

to define the toDateTime function.

In it, we create a date with timestamp 0.

Then we call setSeconds to add secs` seconds to it.

Finally we return the t date.

Conclusion

To convert seconds to a date object with JavaScript, we create a date with timestamp 0 and add the seconds we want to it.

Sometimes, we want to make a time delayed redirect with JavaScript.

In this article, we’ll look at how to make a time delayed redirect with JavaScript.

How to make a time delayed redirect with JavaScript?

To make a time delayed redirect with JavaScript, we call setTimeout.

For instance, we write

setTimeout(() => {
  location.href = "http://www.example.com";
}, 1500);

to call setTimeout with a callback that sets location.href to "http://www.example.com" to redirect to http://www.example.com after 1500ms.

Conclusion

To make a time delayed redirect with JavaScript, we call setTimeout.