通过provide和inject函数可以简便的实现跨级组件通讯

父组件提供

const count = ref(0);
provide('count', count);

const updateCount = (num) => {
  count.value += num;
};
provide('updateCount', updateCount);

子组件或者孙子组件接受

const count = inject('count');
const updateCount = inject('updateCount');

t(‘updateCount’);