vuejs3 - Vue2 is successful in writing like this,but using vue3 will prompt the following questions

Question

Vue2 is successful in writing like this,but using vue3 will prompt the following questions.

TypeError: Cannot read property 'getBanner' of undefined
at _callee$ (Banner.vue?40cf:46)
at tryCatch (runtime.js?96cf:63)
at Generator.invoke [as _invoke] (runtime.js?96cf:293)
at Generator.eval [as next] (runtime.js?96cf:118)
at asyncGeneratorStep (asyncToGenerator.js?1da1:3)
at _next (asyncToGenerator.js?1da1:25)
at eval (asyncToGenerator.js?1da1:32)
at new Promise (<anonymous>)
at eval (asyncToGenerator.js?1da1:21)
at Proxy.getBanner (Banner.vue?40cf:46)

question from:https://stackoverflow.com/questions/65906807/vue2-is-successful-in-writing-like-this-but-using-vue3-will-prompt-the-following

Answer 1

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