this.$message({
  message: "提示信息",
  type: "success"
})

import ElementUI from 'element-ui';

ElementUI.Message({
  message: '提示信息',
  type: 'warning'
});

// message.js
/**
 * @Description: 重写message挂载，实现 Class 的私有属性
 * @param { String } options => 消息内容
 * @param { Boolean } single => 是否只显示一个
 */
import { Message } from 'element-ui';

const showMessage = Symbol('showMessage');

class DonMessage {
  success (options, single = false) {
    this[showMessage]('success', options, single);
  }
  warning (options, single = false) {
    this[showMessage]('warning', options, single);
  }
  info (options, single = false) {
    this[showMessage]('info', options, single);
  }
  error (options, single = true) {
    this[showMessage]('error', options, single);
  }

  [showMessage] (type, options, single) {
    if (single) {
      // 判断是否已存在Message
      if (document.getElementsByClassName('el-message--error').length === 0) {
        Message[type](options);
      }
    } else {
      Message[type](options);
    }
  }
}

// 默认导出 私有 Message 组件
export default new DonMessage();

import DonMessage from '@/message' 

DonMessage.warning('请登录') 

// main.js 
Vue.prototype.$message = DonMessage 

// vue文件中调用
this.$message.warning("请登录")