react js component did mount code example

Example 1: prev props

componentDidUpdate(prevProps) {
  // Utilisation classique (pensez bien à comparer les props) :
  if (this.props.userID !== prevProps.userID) {
    this.fetchData(this.props.userID);
  }
}

Example 2: component did mmount

componentDidUpdate(prevProps, prevState, snapshot)

Example 3: react lifecycle

constructor(props) {
  super(props);
  // Don't call this.setState() here!
  this.state = { counter: 0 };
  this.handleClick = this.handleClick.bind(this);
}