如何在React.js中执行debounce ?

我想撤消handleOnChange。

我尝试debounce(这。handleOnChange, 200)但它不起作用。

function debounce(fn, delay) {
  var timer = null;
  return function() {
    var context = this,
      args = arguments;
    clearTimeout(timer);
    timer = setTimeout(function() {
      fn.apply(context, args);
    }, delay);
  };
}

var SearchBox = React.createClass({
  render: function() {
    return <input type="search" name="p" onChange={this.handleOnChange} />;
  },

  handleOnChange: function(event) {
    // make ajax call
  }
});

当前回答

有点晚了,但应该有帮助。 创建这个类(它是用typescript写的,但是很容易转换成javascript)

export class debouncedMethod<T>{
  constructor(method:T, debounceTime:number){
    this._method = method;
    this._debounceTime = debounceTime;
  }
  private _method:T;
  private _timeout:number;
  private _debounceTime:number;
  public invoke:T = ((...args:any[])=>{
    this._timeout && window.clearTimeout(this._timeout);
    this._timeout = window.setTimeout(()=>{
      (this._method as any)(...args);
    },this._debounceTime);
  }) as any;
}

要使用

var foo = new debouncedMethod((name,age)=>{
 console.log(name,age);
},500);
foo.invoke("john",31);

其他回答

class UserListComponent extends Component {
    constructor(props) {
        super(props);
        this.searchHandler = this.keyUpHandler.bind(this);
        this.getData = this.getData.bind(this);
        this.magicSearch = this.magicSearch.bind(this,500);
    }
    getData = (event) => {
        console.log(event.target.value);
    }
    magicSearch = function (fn, d) {
        let timer;
        return function () {
            let context = this;
            clearTimeout(timer);
            timer = setTimeout(() => {
                fn.apply(context, arguments)
            }, d);
        }
    }
    keyUpHandler = this.magicSearch(this.getData, 500);
    render() {
        return (
             <input type="text" placeholder="Search" onKeyUp={this.searchHandler} />
        )
    }
}

Julen的解决方案有点难以阅读,这里有更清晰和准确的反应代码,供那些根据标题而不是问题的微小细节绊倒他的人使用。

Tl;dr版本:当你要更新到观察者发送调用一个调度方法,反过来实际上会通知观察者(或执行ajax等)

使用示例组件jsfiddle完成jsfiddle

var InputField = React.createClass({

    getDefaultProps: function () {
        return {
            initialValue: '',
            onChange: null
        };
    },

    getInitialState: function () {
        return {
            value: this.props.initialValue
        };
    },

    render: function () {
        var state = this.state;
        return (
            <input type="text"
                   value={state.value}
                   onChange={this.onVolatileChange} />
        );
    },

    onVolatileChange: function (event) {
        this.setState({ 
            value: event.target.value 
        });

        this.scheduleChange();
    },

    scheduleChange: _.debounce(function () {
        this.onChange();
    }, 250),

    onChange: function () {
        var props = this.props;
        if (props.onChange != null) {
            props.onChange.call(this, this.state.value)
        }
    },

});

下面是我想出的一个用debouncer包装另一个类的例子。这使得自己很好地成为一个装饰器/高阶函数:

export class DebouncedThingy extends React.Component {
    static ToDebounce = ['someProp', 'someProp2'];
    constructor(props) {
        super(props);
        this.state = {};
    }
    // On prop maybe changed
    componentWillReceiveProps = (nextProps) => {
        this.debouncedSetState();
    };
    // Before initial render
    componentWillMount = () => {
        // Set state then debounce it from here on out (consider using _.throttle)
        this.debouncedSetState();
        this.debouncedSetState = _.debounce(this.debouncedSetState, 300);
    };
    debouncedSetState = () => {
        this.setState(_.pick(this.props, DebouncedThingy.ToDebounce));
    };
    render() {
        const restOfProps = _.omit(this.props, DebouncedThingy.ToDebounce);
        return <Thingy {...restOfProps} {...this.state} />
    }
}

现在,React和React Native在2019年底有了另一个解决方案:

react-debounce-component

<input>
<Debounce ms={500}>
  <List/>
</Debounce>

它是一个组件,易于使用,体积小,支持广泛

例子:

import React from 'react';
import Debounce from 'react-debounce-component';

class App extends React.Component {
  constructor (props) {
    super(props);
    this.state = {value: 'Hello'}
  }
  render () {
    return (
      <div>
        <input value={this.state.value} onChange={(event) => {this.setState({value: event.target.value})}}/>
        <Debounce ms={1000}>
          <div>{this.state.value}</div>
        </Debounce>
      </div>
    );
  }
}

export default App;

我是这个组件的创建者

我们需要将setter传递给debpublished方法:

以下是StackBlitz的一个例子:

import React from "react";
import debounce from "lodash/debounce";

export default function App() {
  const [state, setState] = React.useState({
    debouncedLog: ""
  });

  const debouncedLog = React.useCallback(
    debounce((setState, log) => {
      setState(prevState => ({
        ...prevState,
        debouncedLog: log
      }));
    }, 500),
    []
  );

  const onChange = React.useCallback(({ target: { value: log } }) => {
    debouncedLog(setState, log); // passing the setState along...
  }, []);
  return (
    <div>
      <input onChange={onChange} style={{ outline: "1px blue solid" }} />

      <pre>Debounced Value: {state.debouncedLog}</pre>
    </div>
  );
}

祝你好运…