如何使用CDN在HTML中加载ES6，React，Babel代码？

Z时代
2024-01-10
分类：问答

我有Codepen代码，我正尝试仅使用三个文件index.html，main.js和style.css在网页上复制它们。我尝试将这些脚本加载到HTML文件的head标签上。

<script src="https://npmcdn.com/babel-transform-in-browser@6.4.6/dist/btib.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/0.14.7/react.min.js"></script>

但是，它不起作用。我得到的只是这个错误

Uncaught SyntaxError: Unexpected token <

有什么必要的CDN脚本文件将此反应代码加载到HTML？

回答：

您需要使用babel standalone脚本来反编译代码，并且需要包含的脚本react and react-dom，使用它们可以正常工作：

<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.24.0/babel.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>

检查设置/ JavaScript，您会发现babel被选择为，codepen自动包含了脚本，但是要在本地运行这些文件，您需要包含standalone script。

1-您需要在呈现反应代码的div之后定义脚本，否则它将引发错误。像这样：

<body> 
   <div id="root"></div> 
   <script type="text/babel" src="pomodoro.js"></script>
</body>

2-使用ReactDOM.render代替React.render。

检查工作代码：

<html>
<head>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.24.0/babel.js"></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js'></script>
</head>
<body>
   <div id='root'></div>
   <script type='text/babel'>
       class SetTimer extends React.Component{
  render(){
    return (
      <div className="set-timer">work <br/> session
          <div className="minus-add">
            <button className="setting-button" id="minus-timer" onClick={this.props.minus}>-</button>
            <button className="setting-button" id="add-timer" onClick={this.props.add}>+</button>
          </div>
      </div>
    );
  }
}
class SetBreak extends React.Component{
  render(){
    return (
      <div className="set-break"> break<br/> session
          <div className="minus-add">
            <button className="setting-button" id="minus-break" onClick={this.props.minusbreak}>-</button>
            <button className="setting-button" id="add-break" onClick={this.props.addbreak}>+</button>
          </div>
      </div>
    );
  }
}
const leftPad = (time)=>{
  return (time<10)? '0'+time :time
}
const TimerDisplay = (props) => (
  <div className="timer-display"><span className="worklabel">Work session time</span><br/>
      {props.currentTime}
      <div className="breaktime"><span className="breaklabel">break session time</span><br/>{props.breakTime}</div>
    </div>
);
// let baseTime= 25;
class App extends React.Component {
  constructor(){
    super();
    this.state = {
      baseTime:25,
      breakTime:5,
      currentTime: moment.duration(25,'minutes'),
      timer:null,
      startbuttonvisible:true,
      pausebuttonvisible:false,
      resumebuttonvisible:false,
      stopbuttonvisible:false,
    }
    this.minus =this.minus.bind(this);
    this.add =this.add.bind(this);
    this.minusbreak =this.minusbreak.bind(this);
    this.addbreak =this.addbreak.bind(this);
    this.startTimer = this.startTimer.bind(this);
    this.pauseTimer = this.pauseTimer.bind(this);
    this.resumeTimer = this.resumeTimer.bind(this);
    this.stopTimer = this.stopTimer.bind(this);
    this.reduceTimer = this.reduceTimer.bind(this);
  }
  add(){
    this.setState({
      baseTime:this.state.baseTime+1
    });
  }
  minus(){
    this.setState({
      baseTime:this.state.baseTime-1
    });
  }
  addbreak(){
    this.setState({
      breakTime:this.state.breakTime+1
    });
  }
  minusbreak(){
    this.setState({
      breakTime:this.state.breakTime-1
    });
  }
  startTimer(){
    this.setState({
      timer: setInterval(this.reduceTimer, 1000),
      startbuttonvisible:false,
      pausebuttonvisible:true,
      stopbuttonvisible:true,
    });
  }
  pauseTimer(){
    clearInterval(this.state.timer);
    this.setState({
      pausebuttonvisible:false,
      resumebuttonvisible:true,
    });
  }
  resumeTimer(){
    this.setState({
      timer: setInterval(this.reduceTimer, 1000),
      startbuttonvisible:false,
      pausebuttonvisible:true,
      stopbuttonvisible:true,
      resumebuttonvisible:false,
    });
  }
  stopTimer(){
    clearInterval(this.state.timer);
    this.setState({
      baseTime:25,
      timer: null,
      startbuttonvisible:true,
      pausebuttonvisible:false,
      stopbuttonvisible:false,
      resumebuttonvisible:false,
    });
  }
  reduceTimer(){
    if(this.state.baseTime === 0) return;
    const newTime = this.state.baseTime - 1;
    this.setState({
      baseTime: newTime,
    });
  }
  render() {
    return (
      <div className="container">
         <div className="timebox">
            <div className="header">
                    Pomodoro Clock
            </div>
            <TimerDisplay currentTime={this.state.baseTime} breakTime={this.state.breakTime}/>
            <div id="action-title">
                <small>SETTINGS</small>
            </div>
            <div className="actions">
              <SetTimer minus={this.minus} add={this.add}/>
              <SetBreak minusbreak={this.minusbreak} addbreak={this.addbreak}/>
            </div>
           <div className="timer-control">
            {this.state.startbuttonvisible ? <button id="start-timer" onClick={this.startTimer}>
                START
            </button> : null}
           {this.state.pausebuttonvisible ? <button id="pause-timer" onClick={this.pauseTimer}>
                PAUSE
            </button>: null}
           {this.state.resumebuttonvisible ? <button id="resume-timer" onClick={this.resumeTimer}>
                RESUME
            </button>: null}
           {this.state.stopbuttonvisible ? <button id="stop-timer" onClick={this.stopTimer}>
                STOP
            </button>: null}
           </div>
        </div>
      </div>
    );
  }
}
ReactDOM.render(
  <App />,
  document.getElementById('root')
);
   </script>
</body>
</html>