關於 React 小書：評論功能（六）：刪除評論、預防 XSS

Comment.js

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

class Comment extends Component {
  static propTypes = {
    comment: PropTypes.object.isRequired,
    onDeleteComment: PropTypes.func,
    index: PropTypes.number
  }

  constructor() {
    super()
    this.state = {timeString: ''}
  }

  componentWillMount() {
    this._updateTimeString()
    this._timer = setInterval(
      this._updateTimeString.bind(this),
      5000
    )
  }

  componentWillUnmount() {
    clearInterval(this._timer)
  }

  _updateTimeString() {
    const comment = this.props.comment
    const duration = (+Date.now() - comment.createdTime) / 1000
    this.setState({
      timeString: duration > 60
        ? `${Math.round(duration / 60)} 分鐘前`
        : `${Math.round(Math.max(duration, 1))} 秒前`
    })
  }

  _getProcessedContent (content) {
    return content
      .replace(/`([\S\s]+?)`/g, '<code>$1</code>')
  }

  handleDeleteComment () {
    if (this.props.onDeleteComment) {
      this.props.onDeleteComment(this.props.index)
    }
  }

  render() {
    return (
      <div className='comment'>
        <div className='comment-user'>
          <span>{this.props.comment.username} </span>：
        </div>
        <p dangerouslySetInnerHTML={{
          __html: this._getProcessedContent(this.props.comment.content)
        }} />
        <span className='comment-createdtime'>
          {this.state.timeString}
        </span>
        <span
          onClick={this.handleDeleteComment.bind(this)}
          className='comment-delete'>
          刪除
        </span>
      </div>
    )
  }
}

export default Comment