stack/v1/packages/mosaic/framework/skills/vueuse-functions/references/reactivePick.md

category

category
Reactivity

reactivePick

Reactively pick fields from a reactive object.

Usage

Basic Usage

import { reactivePick } from '@vueuse/core';

const obj = reactive({
  x: 0,
  y: 0,
  elementX: 0,
  elementY: 0,
});

const picked = reactivePick(obj, 'x', 'elementX'); // { x: number, elementX: number }

Predicate Usage

import { reactivePick } from '@vueuse/core';

const source = reactive({
  foo: 'foo',
  bar: 'bar',
  baz: 'baz',
  qux: true,
});
const state = reactivePick(source, (value, key) => key !== 'bar' && value !== true);
// { foo: string, baz: string }
source.qux = false;
// { foo: string, baz: string, qux: boolean }

Scenarios

Selectively passing props to child

<script setup lang="ts">
import { reactivePick } from '@vueuse/core';

const props = defineProps<{
  value: string;
  color?: string;
  font?: string;
}>();

const childProps = reactivePick(props, 'color', 'font');
</script>

<template>
  <div>
    <!-- only passes "color" and "font" props to child -->
    <ChildComp v-bind="childProps" />
  </div>
</template>

Selectively wrap reactive object

Instead of doing this

import { useElementBounding } from '@vueuse/core';
import { reactive } from 'vue';

const { height, width } = useElementBounding(); // object of refs
const size = reactive({ height, width });

Now we can just have this

import { reactivePick, useElementBounding } from '@vueuse/core';

const size = reactivePick(useElementBounding(), 'height', 'width');

Type Declarations

export type ReactivePickReturn<T extends object, K extends keyof T> = {
  [S in K]: UnwrapRef<T[S]>;
};
export type ReactivePickPredicate<T> = (value: T[keyof T], key: keyof T) => boolean;
export declare function reactivePick<T extends object, K extends keyof T>(
  obj: T,
  ...keys: (K | K[])[]
): ReactivePickReturn<T, K>;
export declare function reactivePick<T extends object>(
  obj: T,
  predicate: ReactivePickPredicate<T>,
): ReactivePickReturn<T, keyof T>;