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watchThrottled

Category
Export Size
824 B
Last Changed
8 months ago
Alias
throttledWatch

Throttled watch.

Demo

Delay is set to 1000ms for this demo.

Input:

Times Updated: 0

Usage

Similar to watch, but offering an extra option throttle which will be applied to the callback function.

ts
import { watchThrottled } from '@vueuse/core'

watchThrottled(
  source,
  () => { console.log('changed!') },
  { throttle: 500 },
)
import { watchThrottled } from '@vueuse/core'

watchThrottled(
  source,
  () => { console.log('changed!') },
  { throttle: 500 },
)

It's essentially a shorthand for the following code:

ts
import { throttleFilter, watchWithFilter } from '@vueuse/core'

watchWithFilter(
  source,
  () => { console.log('changed!') },
  {
    eventFilter: throttleFilter(500),
  },
)
import { throttleFilter, watchWithFilter } from '@vueuse/core'

watchWithFilter(
  source,
  () => { console.log('changed!') },
  {
    eventFilter: throttleFilter(500),
  },
)

Type Declarations

typescript
export interface WatchThrottledOptions<Immediate>
  extends WatchOptions<Immediate> {
  throttle?: MaybeComputedRef<number>
  trailing?: boolean
  leading?: boolean
}
export declare function watchThrottled<
  T extends Readonly<WatchSource<unknown>[]>,
  Immediate extends Readonly<boolean> = false
>(
  sources: [...T],
  cb: WatchCallback<MapSources<T>, MapOldSources<T, Immediate>>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export declare function watchThrottled<
  T,
  Immediate extends Readonly<boolean> = false
>(
  source: WatchSource<T>,
  cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export declare function watchThrottled<
  T extends object,
  Immediate extends Readonly<boolean> = false
>(
  source: T,
  cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export { watchThrottled as throttledWatch }
export interface WatchThrottledOptions<Immediate>
  extends WatchOptions<Immediate> {
  throttle?: MaybeComputedRef<number>
  trailing?: boolean
  leading?: boolean
}
export declare function watchThrottled<
  T extends Readonly<WatchSource<unknown>[]>,
  Immediate extends Readonly<boolean> = false
>(
  sources: [...T],
  cb: WatchCallback<MapSources<T>, MapOldSources<T, Immediate>>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export declare function watchThrottled<
  T,
  Immediate extends Readonly<boolean> = false
>(
  source: WatchSource<T>,
  cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export declare function watchThrottled<
  T extends object,
  Immediate extends Readonly<boolean> = false
>(
  source: T,
  cb: WatchCallback<T, Immediate extends true ? T | undefined : T>,
  options?: WatchThrottledOptions<Immediate>
): WatchStopHandle
export { watchThrottled as throttledWatch }

Source

SourceDemoDocs

Contributors

Anthony Fu
sun0day
丶远方
lvjiaxuan
Joe Zimmerman
webfansplz

Changelog

v8.9.1 on 7/8/2022
a9ccc - feat(all): use MaybeComputedRef (#1768)
v8.7.0 on 6/16/2022
bb0ac - fix(watch*): fix T type for WatchCallback (#1692)

Released under the MIT License.