Vue creates a global function and calls it, always reporting an error. Besides this method, is there any other way to create a local component

Does your so-called global function depend on Vue m?

If you don't rely on it, save a separate file for export and import where you need it.

Where is this method written?

Did you import Vue?

import Vue from 'vue'

//Global approach

Api = {
  // 支付方式
  GetPayType: function (tyep) {
    tyep = tyep * 1
    switch (tyep) {
      case 0:
        return '试听'
        break
      case 1:
        return '微信'
        break
      case 2:
        return '支付宝'
        break
      case 3:
        return '银行卡'
        break
      case 4:
        return '现金'
        break
    }
  },
}
export default Api

// main.js

// 注册全局方法
import Api from "./utils/api";  
Vue.prototype.$api = Api; // 方法

//Use in build

this.$api.GetPayType()