Componentdidupdate() React Code Example


Example 1: component did update arguments


componentDidUpdate(prevProps, prevState) {
  // only update chart if the data has changed
  if (prevProps.data !== this.props.data) {
    this.chart = c3.load({
      data: this.props.data
    });
  }
}

Example 2: componentDidUpdate


componentDidUpdate(prevProps, prevState) {
  if (prevState.pokemons !== this.state.pokemons) {
    console.log('pokemons state has changed.')
  }
}

Example 3: react lifecycle


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

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