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Scroll to the bottom of a div in React:

1. divAdd an element at the bottom of the .
2. Set a on the bottom element ref.
3. When an event occurs, the method refof the object is called scrollIntoView().

import {useEffect, useRef, useState} from 'react';

export default function App() {
  const bottomRef = useRef(null);

  const [messages, setMessages] = useState([]);

  useEffect(() => {
    // 👇️ simulate chat messages flowing in
    setInterval(
      () =>
        setMessages(current => [
          ...current,
          'Lorem ipsum dolor sit amet consectetur, adipisicing elit. Porro, quaerat eum id obcaecati, magnam voluptatum dolorem sunt, omnis sed consectetur necessitatibus blanditiis ipsa? Cumque architecto, doloribus mollitia velit non sint!',
        ]),
      600,
    );
  }, []);

  useEffect(() => {
    // 👇️ scroll to bottom every time messages change
    bottomRef.current?.scrollIntoView({behavior: 'smooth'});
  }, [messages]);

  return (
    <div>
      <h2>Top of the page</h2>

      <div>
        {messages.map((message, index) => {
          return <p key={index}>{message}</p>;
        })}

        <div ref={bottomRef} />
      </div>
    </div>
  );
}

This code shows how to scroll to the bottom of the div each time a new chat message flows in.

The first call to useEffectthe hook simulates new messages appearing every 600 milliseconds.

We useRefinitialize a ref using the hook.

useRef()The hook can be passed an initial value as an argument. The hook returns a mutable ref object whose .current property is initialized to the passed argument.

Note that we have to access currentthe property of the ref object to access the div element on which we set the ref attribute.

When we pass a ref prop to an element, for example <div ref={myRef} />, React .currentsets the property of the ref object to the corresponding DOM node.

We added the message state variable as a dependency in the second useEffecthook because we want to re-run the code in the hook every time the message changes.

useEffect(() => {
  bottomRef.current?.scrollIntoView({behavior: 'smooth'});
}, [messages]);

We use scrollIntoViewthe method to scroll to the bottom of the chat message container div element.

behaviorProperty specifies whether scrolling should be smooth ( smooth) or immediate ( auto).

behaviorThe default value of the property is auto.

Every time the message changes, useEffectthe hook is re-run and we call scrollIntoView()the method to scroll to the bottom of the div and display the latest message.