error message
Reason: Probably the vue version is inconsistent.
The vue imported by the html page when I reported an error
<script src="https://unpkg.com/vue/dist/vue.js"></script>
Just change to the version starting with 2
<script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/vue.js"></script>
Finish! ! !
hy:10
自律是自由的根基。---苏格拉底