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
}
});
下面是一个使用@Abra方法封装在函数组件中的代码片段
(我们使用织物的UI,只是用一个简单的按钮替换它)
import React, { useCallback } from "react";
import { debounce } from "lodash";
import { PrimaryButton, DefaultButton } from 'office-ui-fabric-react/lib/Button';
const debounceTimeInMS = 2000;
export const PrimaryButtonDebounced = (props) => {
const debouncedOnClick = debounce(props.onClick, debounceTimeInMS, { leading: true });
const clickHandlerDebounced = useCallback((e, value) => {
debouncedOnClick(e, value);
},[]);
const onClick = (e, value) => {
clickHandlerDebounced(e, value);
};
return (
<PrimaryButton {...props}
onClick={onClick}
/>
);
}
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);
你可以在ReactJS钩子中使用一个use-debounce包。
从包的README:
import { useDebounce } from 'use-debounce';
export default function Input() {
const [text, setText] = useState('Hello');
const [value] = useDebounce(text, 1000);
return (
<div>
<input
defaultValue={'Hello'}
onChange={(e) => {
setText(e.target.value);
}}
/>
<p>Actual value: {text}</p>
<p>Debounce value: {value}</p>
</div>
);
}
从上面的示例中可以看到,它设置为每秒钟更新一次变量值(1000毫秒)。
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…