reactjs - componentDidMount : Can't call setState (or forceUpdate) on an unmounted component

我在 componentDidMount 中获取数据并更新状态，出现了著名的警告:



我的代码如下:

componentDidMount() {
    let self = this;

    let apiBaseUrl = Config.serverUrl;
    axios.get( apiBaseUrl + '/dataToBeFetched/' )
        .then( function(response) {
            self.setState( { data: response.data } );;
        } );
}

导致此警告的原因是什么？获取数据和更新状态的最佳方法是什么？

最佳答案

基于以前的答案，我做了以下工作正常:

constructor(props) {
   this.state = {isMounted: false}
}

componentDidMount() {
    let apiBaseUrl = Config.serverUrl;
    this.setState( { isMounted: true }, () => {
        axios.get( apiBaseUrl + '/dataToBeFetched/' )
            .then( (response) => { // using arrow function ES6
                if( this.state.isMounted ) {
                    this.setState( { pets: response.data } );
                }
            } ).catch( error => {
                // handle error
        } )
    } );
}

componentWillUnmount() {
    this.setState( { isMounted: false } )
}

另一个更好的解决方案是取消卸载中的请求，如下所示:

constructor(props) {
    this._source = axios.CancelToken.source();
}

componentDidMount() {
    let apiBaseUrl = Config.serverUrl;
    axios.get( apiBaseUrl + '/dataToBeFetched/', { cancelToken: this._source.token } )
        .then( (response) => { // using arrow function ES6
            if( this.state.isMounted ) {
                this.setState( { pets: response.data } );
            }
        } ).catch( error => {
            // handle error
    } );
}

componentWillUnmount() {
    this._source.cancel( 'Operation canceled due component being unmounted.' )
}

关于reactjs - componentDidMount : Can't call setState (or forceUpdate) on an unmounted component，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/50396375/