ReadMoreLess

read-more-less.js

import React, {Component} from 'react';
import PropTypes from 'prop-types';

export default class ReadMoreLess extends Component {
  static propTypes = {
    text: PropTypes.string.isRequired
  };

  state = {
    expanded: false
  };

  toggle = () => {
    this.setState(prevState => ({
      expanded: !prevState.expanded
    }));
  };

  render() {
    const text = this.state.expanded
      ? this.props.text
      : this.props.text.slice(0, 30);
    return (
      <div>
        {text}
        {!this.state.expanded ? (
          <span>
            ... <a onClick={this.toggle}>Read more</a>
          </span>
        ) : (
          <span>
            {' '}
            <a onClick={this.toggle}>Read less</a>
          </span>
        )}
      </div>
    );
  }
}

usage.js

<ReadMoreLess text="Keyholder allows API developers to focus on building great APIs by providing a simple and free way to generate and authenticate API keys for their services." />