关于vue.js:vue2和vue3-通过函数调用一个组件

实现一个简略的弹窗组件：

1. vue2 函数式组件写法，通过extend办法：
   创立ui.vue文件，寄存咱们的组件，如下：

<template>
    <div class="dialog">
        <div class="dialog-body">
            <div class="dialog-content">
                你好
            </div>
            <div class="dialog-footer" @click="close">敞开</div>
        </div>
    </div>
</template>
<script></script>
<style lang="scss" scoped>
    .dialog {
        width: 100vw;
        height: 100vh;
        position: fixed;
        top: 0;
        left: 0;
        background-color: rgba($color: #000000, $alpha: 0.2);
        &-body {
            width: 500px;
            height: 300px;
            position: absolute;
            left: 50%;
            top: 50%;
            transform: translate(-50%, -50%);
            background-color: #fff;
            border-radius: 4px;
            padding: 10px;
        }
        &-content {
            height: 250px;
        }   
        &-footer {
            height: 50px;
        }
    }
</style>

同级目录下创立一个index.js，内容如下;

import UI from "./ui.vue"
import Vue from "vue"
function openDialog() {
    let install = null
    return new Promise((resolve, reject) => {
        const UIconstructor = Vue.extend(UI)
        install = new UIconstructor({
            methods: {
                close(e) {
                    document.body.removeChild(install.$el)
                    resolve(e)
                },
            },
        }).$mount();
        document.body.appendChild(install.$el)
    })
}
export default openDialog

在其余页面间接引入调用openDialog即可

2. vue3中实现，ui.vue不变，index.js批改如下：

import UI from "./ui.vue"
import { createApp } from "vue"

export default function openDialog() {
  // 创立一个节点，并将组件挂载下来
  const mountNode = document.createElement("div")
  document.body.appendChild(mountNode)
  const app: any = createApp(UI, {
    close: () => {
      app.unmount()
      document.body.removeChild(mountNode)
    },
  })
  app.mount(mountNode)
}