because vue version 2.5 or above is required to use element-ui, this error is reported after updating the vue, refresh page separately. I really don"t understand.
ide/reactivity.html-sharp%E5%A3%B0%E6%98%8E%E5%93%8D%E5%BA%94%E5%BC%8F%E5%B1%9E%E6%80%A7" rel=" nofollow noreferrer "> links on the diagram