Vue download base64 file

<a ref="download" v-show="false" :href="downloadUrl" :download="downloadfilename"></a>

export default {
  data () {
    return {
      downloadUrl: null,
      downloadfilename: null
    }
  },
  mounted () {
    let base64Data = 'data:image/png;base64,iVBORw0KGgoAAAAN...'
    console.log(base64Data)
    this.downLoadImage(base64Data)
  },
  methods: {
    downLoadImage (imgUrl) {
      let timestamp = new Date().getTime()
      let name = imgUrl.substring(22, 30) + timestamp + '.png'
      this.downloadUrl = imgUrl
      this.downloadfilename = name
      setTimeout(() => {
        this.$refs.download.click()
      }, 200)
    }
  }
}