主题
watchIgnorable
可忽略的监视
¥Ignorable watch
示例
用法
¥Usage
扩展 watch 返回额外的 ignoreUpdates(updater) 和 ignorePrevAsyncUpdates() 以忽略对源的特定更新。
¥Extended watch that returns extra ignoreUpdates(updater) and ignorePrevAsyncUpdates() to ignore particular updates to the source.
ts
import { watchIgnorable } from '@vueuse/core'
import { nextTick, ref } from 'vue'
const source = ref('foo')
const { stop, ignoreUpdates } = watchIgnorable(
source,
v => console.log(`Changed to ${v}!`),
)
source.value = 'bar'
await nextTick() // logs: Changed to bar!
ignoreUpdates(() => {
source.value = 'foobar'
})
await nextTick() // (nothing happened)
source.value = 'hello'
await nextTick() // logs: Changed to hello!
ignoreUpdates(() => {
source.value = 'ignored'
})
source.value = 'logged'
await nextTick() // logs: Changed to logged!冲水时间
¥Flush timing
watchIgnorable 接受与 watch 相同的选项并使用相同的默认值。因此，默认情况下，可组合项使用 flush: 'pre' 工作。
¥watchIgnorable accepts the same options as watch and uses the same defaults. So, by default the composable works using flush: 'pre'.
ignorePrevAsyncUpdates
此函数仅适用于异步刷新 'pre' 和 'post'。如果使用 flush: 'sync'，则 ignorePrevAsyncUpdates() 是无操作，因为监视将在每次更新源后立即触发。它仍然提供同步刷新，因此代码可以更通用。
¥This feature is only for async flush 'pre' and 'post'. If flush: 'sync' is used, ignorePrevAsyncUpdates() is a no-op as the watch will trigger immediately after each update to the source. It is still provided for sync flush so the code can be more generic.
ts
import { watchIgnorable } from '@vueuse/core'
import { nextTick, ref } from 'vue'
const source = ref('foo')
const { ignorePrevAsyncUpdates } = watchIgnorable(
source,
v => console.log(`Changed to ${v}!`),
)
source.value = 'bar'
await nextTick() // logs: Changed to bar!
source.value = 'good'
source.value = 'by'
ignorePrevAsyncUpdates()
await nextTick() // (nothing happened)
source.value = 'prev'
ignorePrevAsyncUpdates()
source.value = 'after'
await nextTick() // logs: Changed to after!推荐读物
¥Recommended Readings
类型声明
显示类型声明
typescript
export type IgnoredUpdater = (updater: () => void) => void
export interface WatchIgnorableReturn {
ignoreUpdates: IgnoredUpdater
ignorePrevAsyncUpdates: () => void
stop: WatchStopHandle
}
export declare function watchIgnorable<
T extends Readonly<WatchSource<unknown>[]>,
Immediate extends Readonly<boolean> = false,
>(
sources: [...T],
cb: WatchCallback<MapSources<T>, MapOldSources<T, Immediate>>,
options?: WatchWithFilterOptions<Immediate>,
): WatchIgnorableReturn
export declare function watchIgnorable<
T,
Immediate extends Readonly<boolean> = false,
>(
source: WatchSource<T>,
cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
options?: WatchWithFilterOptions<Immediate>,
): WatchIgnorableReturn
export declare function watchIgnorable<
T extends object,
Immediate extends Readonly<boolean> = false,
>(
source: T,
cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
options?: WatchWithFilterOptions<Immediate>,
): WatchIgnorableReturn
export { watchIgnorable as ignorableWatch }