主题
computedWithControl
显式定义计算的依赖。
¥Explicitly define the dependencies of computed.
用法
¥Usage
ts
import { computedWithControl } from '@vueuse/core'
const source = ref('foo')
const counter = ref(0)
const computedRef = computedWithControl(
() => source.value, // watch source, same as `watch`
() => counter.value, // computed getter, same as `computed`
)
js
import { computedWithControl } from '@vueuse/core'
const source = ref('foo')
const counter = ref(0)
const computedRef = computedWithControl(
() => source.value, // watch source, same as `watch`
() => counter.value,
)
这样,counter
的更改不会触发 computedRef
更新,但 source
引用会触发。
¥With this, the changes of counter
won't trigger computedRef
to update but the source
ref does.
ts
console.log(computedRef.value) // 0
counter.value += 1
console.log(computedRef.value) // 0
source.value = 'bar'
console.log(computedRef.value) // 1
手动触发
¥Manual Triggering
你还可以通过以下方式手动触发计算的更新:
¥You can also manually trigger the update of the computed by:
ts
const computedRef = computedWithControl(
() => source.value,
() => counter.value,
)
computedRef.trigger()
警告
手动触发仅适用于 Vue 3
¥Manual triggering only works for Vue 3
类型声明
typescript
export interface ComputedWithControlRefExtra {
/**
* Force update the computed value.
*/
trigger: () => void
}
export interface ComputedRefWithControl<T>
extends ComputedRef<T>,
ComputedWithControlRefExtra {}
export interface WritableComputedRefWithControl<T>
extends WritableComputedRef<T>,
ComputedWithControlRefExtra {}
export declare function computedWithControl<T, S>(
source: WatchSource<S> | WatchSource<S>[],
fn: ComputedGetter<T>,
): ComputedRefWithControl<T>
export declare function computedWithControl<T, S>(
source: WatchSource<S> | WatchSource<S>[],
fn: WritableComputedOptions<T>,
): WritableComputedRefWithControl<T>
export { computedWithControl as controlledComputed }