我如何专门检查Netinfo反应的URL

Question

这是您当前使用的代码来交换和验证连接，我认为它正常工作：

  constructor() {
    super();
    this.state = {
      connection_Status: ""
    }
  }
  componentDidMount() {
    NetInfo.isConnected.addEventListener(
      'connectionChange',
      this._handleConnectivityChange
    );
    NetInfo.isConnected.fetch().done((isConnected) => {
      if (isConnected == true) {
        this.setState({ connection_Status: "Online" })
      }
      else {
        this.setState({ connection_Status: "Offline." })
      }
    });
    SplashScreen.hide();
  }
  componentWillUnmount() {
    NetInfo.isConnected.removeEventListener(
      'connectionChange',
      this._handleConnectivityChange
    );
  }
  _handleConnectivityChange = (isConnected) => {
    if (isConnected == true) {
      this.setState({ connection_Status: "Online" })
    }
    else {
      this.setState({ connection_Status: "Offline." })
    }
  };

如何检查URL？我考虑了现在使用它，但是我无法实施

let req = await fetch('https://www.someurl.com'); let isConnected = req.status === 200;

对不起，我是新手反应的

Answer 1

提取返回承诺，

因此，您可以这样使用它，

fetch('https://www.someurl.com')
 .then((res) =>{
        this.setState({status:res.status});
     })
    .then((res) => {
      //do somthing with responce
    })
    .catch((error) => {
      console.error(error);
    });