componentWillUpdate is deprecated in React, how can I replace it?

Question

React 16.3.0 was released and there were changes in React lifecycles.

React does not recommend to use componentWillMount, componentWillReceiveProps, componentWillUpdate.

In that case, what should I use instead of componentWillUpdate? For example, in the following code how can I replace componentWillUpdate?

import React from "react";
import Modal from "./Modal";

class ModalContainer extends React.Component {
  state = {
    openModal: false
  };
  onClick = () => {
    this.setState({
      openModal: !this.state.openModal
    });
  };

  escapeKey = e => {
    if (e.key === "Escape" && this.state.openModal === true) {
      this.setState({
        openModal: !this.state.openModal
      });
    }
  };
  componentDidMount() {
    document.body.classList.add("no-scroll");
    this.componentWillUpdate(this.state, this.state);
  }
  componentWillUpdate(p, c) {
    if (c.openModal) {
      window.addEventListener("keyup", this.escapeKey);
    } else {
      window.removeEventListener("keyup", this.escapeKey);
    }
  }
  componentWillUnmount() {
    window.removeEventListener("keyup", this.escapeKey);
  }

  render(props) {
    return (
      <div className="ModalContainer">
        <a className={`ModalContainer-trigger`} onClick={this.onClick}>
          click here to open the modal
        </a>
        {this.state.openModal && (
          <Modal
            onClick={this.onClick}
            in={!!this.state.openModal}
            {...this.props}
          />
        )}{" "}
      </div>
    );
  }
}
export default ModalContainer;

Thank you

Answer 1

Take a look at getSnapshotBeforeUpdate

https://reactjs.org/docs/react-component.html#getsnapshotbeforeupdate

getSnapshotBeforeUpdate() is invoked right before the most recently rendered output is committed to e.g. the DOM. It enables your component to capture some information from the DOM (e.g. scroll position) before it is potentially changed.

Btw, I think there's not much use case to use such method.

You can still use componentDidUpdate if you want to have side effects after any states changed.

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This answer based on React16.6.3