安装插件

 npm i qrcode -s

引入插件

import Vue from 'vue'
import App from './App.vue'
import  QRCode  from 'qrcode'

Vue.use(QRCode)

Vue.prototype.$QRCode = QRCode

new Vue({
  el: '#app',
  a:'123',
  render: h => h(App)
})

使用

<template>
  <div id="app">
    <canvas id="canvas"></canvas>
  </div>
</template>

<script>
import popup from "./components/popup.vue";
export default {
  components: { popup },
  name: "app",
  data() {
    return {};
  },
  mounted: function () {
    var cavas = document.getElementById("canvas")
    this.$QRCode.toCanvas(canvas,'https://www.xiangcaowuyu.net')
  },
  computed: {
   
  },
  methods: {
    
  },
};
</script>

<style>
#app {
  font-family: "Avenir", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}
</style>