usePrevious

类别

Utilities

导出体积

251 B

上次更改

5 days ago

保存 ref 的先前值。

用法

import { usePrevious } from '@vueuse/core'
import { shallowRef } from 'vue'

const counter = shallowRef('Hello')
const previous = usePrevious(counter)

console.log(previous.value) // undefined

counter.value = 'World'

console.log(previous.value) // Hello

类型声明

/**
 * 保存 ref 的前一个值。
 *
 * @see   {@link https://vueuse.org/usePrevious}
 */
export declare function usePrevious<T>(
  value: MaybeRefOrGetter<T>,
): Readonly<ShallowRef<T | undefined>>
export declare function usePrevious<T>(
  value: MaybeRefOrGetter<T>,
  initialValue: T,
): Readonly<ShallowRef<T>>

源码

源码 • 文档

贡献者

一纸忘忧

Anthony Fu

IlyaL

Anthony Fu

更新日志

v12.8.0 on 3/5/2025

7432f - feat(types): deprecate MaybeRef and MaybeRefOrGetter in favor of Vue's native (#4636)

v12.0.0-beta.1 on 11/21/2024

0a9ed - feat!: drop Vue 2 support, optimize bundles and clean up (#4349)

v10.0.0-beta.4 on 4/13/2023

4d757 - feat(types)!: rename MaybeComputedRef to MaybeRefOrGetter

10e98 - feat(toRef)!: rename resolveRef to toRef