useDebounceFn

Demo

此示範延遲設定為 1000 毫秒，最大等待時間設定為 5000 毫秒。

按鈕點擊次數：0

事件處理器呼叫次數：0

Usage

import { useDebounceFn, useEventListener } from '@vueuse/core'

const debouncedFn = useDebounceFn(() => {
  // do something
}, 1000)

useEventListener(window, 'resize', debouncedFn)

您也可以傳遞第三個參數，設定最大等待時間，類似於 lodash debounce

import { useDebounceFn, useEventListener } from '@vueuse/core'

// If no invokation after 5000ms due to repeated input,
// the function will be called anyway.
const debouncedFn = useDebounceFn(() => {
  // do something
}, 1000, { maxWait: 5000 })

useEventListener(window, 'resize', debouncedFn)

或者，您可以透過 Promise 操作取得函式的回傳值。

import { useDebounceFn } from '@vueuse/core'

const debouncedRequest = useDebounceFn(() => 'response', 1000)

debouncedRequest().then((value) => {
  console.log(value) // 'response'
})

// or use async/await
async function doRequest() {
  const value = await debouncedRequest()
  console.log(value) // 'response'
}

由於在開發者不需要回傳值時，未處理的拒絕錯誤非常惱人，因此如果函式被取消，預設情況下 Promise 將**不會**被拒絕。您需要指定選項 rejectOnCancel: true 以捕獲拒絕。

import { useDebounceFn } from '@vueuse/core'

const debouncedRequest = useDebounceFn(() => 'response', 1000, { rejectOnCancel: true })

debouncedRequest()
  .then((value) => {
    // do something
  })
  .catch(() => {
    // do something when canceled
  })

// calling it again will cancel the previous request and gets rejected
setTimeout(debouncedRequest, 500)

Type Declarations

typescript

/**
 * Debounce execution of a function.
 *
 * @see https://vueuse.dev.org.tw/useDebounceFn
 * @param  fn          A function to be executed after delay milliseconds debounced.
 * @param  ms          A zero-or-greater delay in milliseconds. For event callbacks, values around 100 or 250 (or even higher) are most useful.
 * @param  options     Options
 *
 * @return A new, debounce, function.
 */
export declare function useDebounceFn<T extends FunctionArgs>(
  fn: T,
  ms?: MaybeRefOrGetter<number>,
  options?: DebounceFilterOptions,
): PromisifyFn<T>