vue3---getCurrentInstance

父组件中：

1.setup��法糖中导入子组件

2.在子组件标签上绑定ref值

3.setup内部从vue中按需导出 getCurrentInstance 方法

4.调用getCurrentInstance方法导出proxy

5.通过proxy.$refs.子组件ref名.子组件内属性/方法 实现调用

                子组件count+1   import { getCurrentInstance, ComponetInternalInstance,ref } from "vue";import Child from "./zi.vue";const child = ref(null) // as ComponetInternalInstance表示类型断言，ts时使用。否则报错，proxy为nullconst { proxy } = getCurrentInstance() as ComponetInternalInstance;function changeChildren() {  proxy.$refs.child.count += 1;  //也可以使用ref数据.value的形式调用：  //child.value.count += 1  console.log(child.value.name)} 

main.js

import api from "./utils/api.js"import StringUtil from "./utils/StringUtil.js"app.config.globalProperties.api = api;app.config.globalProperties.StringUtil = StringUtil;

import {getCurrentInstance } from 'vue';const { proxy } = getCurrentInstance();console.log(proxy.api);console.log(proxy.StringUtil.isBlank('1'));

方式一、通过 getCurrentInstance 方法获取当前组件实例，从而获取 route 和 router

Html

    import { defineComponent, getCurrentInstance } from 'vue'export default defineComponent({  name: 'About',  setup(){    const { proxy } = getCurrentInstance()    console.log(proxy.$root.$route)    console.log(proxy.$root.$router)    return {}  }})

方式二：通过从路由中导入 useRoute useRouter 使用 route 和 router。 官方Api

Html

import { defineComponent } from ‘vue’

import { useRoute, useRouter } from ‘vue-router’

export default defineComponent({

setup () {

const $route = useRoute()

const r o u t e r = u s e R o u t e r ( ) c o n s o l e . l o g ( router = useRouter() console.log( router=useRouter()console.log(route)

console.log($router)

}

})