Vue 3 中监听多个数据变化的几种方法

1. 使用 watch监听多个 ref/reactive 数据

import { ref, watch } from 'vue'

export default {
  setup() {
    const count = ref(0)
    const name = ref('')
    const user = reactive({ age: 20 })

    // 监听多个数据源
    watch(
      [count, name, () => user.age], // 数组形式传入多个数据源
      ([newCount, newName, newAge], [oldCount, oldName, oldAge]) => {
        console.log('count changed:', newCount, oldCount)
        console.log('name changed:', newName, oldName)
        console.log('age changed:', newAge, oldAge)
        // 执行相关操作
      }
    )

    return { count, name, user }
  }
}

2. 使用 watchEffect自动追踪依赖

import { ref, watchEffect } from 'vue'

export default {
  setup() {
    const count = ref(0)
    const name = ref('')
    const active = ref(false)

    watchEffect(() => {
      // 这里会自动追踪所有使用到的响应式数据
      console.log('数据变化:', count.value, name.value, active.value)
      // 执行相关操作
    })

    return { count, name, active }
  }
}

3. 监听对象多个属性

import { reactive, watch } from 'vue'

export default {
  setup() {
    const state = reactive({
      count: 0,
      name: '',
      active: false
    })

    // 监听对象多个属性
    watch(
      () => [state.count, state.name],
      ([newCount, newName], [oldCount, oldName]) => {
        console.log('count or name changed')
      }
    )

    return { state }
  }
}