How to correctly catch change/focusOut event on text input in React.js?

I've got a form, in which I want to handle change event on text inputs, but React onChange triggering on key down (opposite to native JS, that triggers change event when an input field is out of focus).

Is there a React way to do what I want?

Solution 1:

If you want to only trigger validation when the input looses focus you can use onBlur.

React uses onFocus and onBlur instead of onFocusIn and onFocusOut. All React events are normalized to bubble, so onFocusIn and onFocusOut are not needed/supported by React. 2

Solution 2:

Its late, yet it's worth your time nothing that, there are some differences in browser level implementation of focusin and focusout events and react synthetic onFocus and onBlur. focusin and focusout actually bubble, while onFocus and onBlur dont. So there is no exact same implementation for focusin and focusout as of now for react. Anyway most cases will be covered in onFocus and onBlur.

Solution 3:

You'd need to be careful as onBlur has some caveats in IE11 (How to use relatedTarget (or equivalent) in IE?, https://developer.mozilla.org/en-US/docs/Web/API/MouseEvent/relatedTarget).

There is, however, no way to use onFocusOut in React as far as I can tell. See the issue on their github https://github.com/facebook/react/issues/6410 if you need more information. (see below for an update on this)

UPDATE:

As of React 17, the events have been updated - see PR for use focusin/focusout for onFocus/onBlur. However as the page listing breaking changes mentions:

Although React 17 switched from focus to focusin under the hood for the onFocus event, note that this has not affected the bubbling behavior. In React, onFocus event has always bubbled, and it continues to do so in React 17 because generally it is a more useful default. See this sandbox for the different checks you can add for different particular use cases.