问getAccounts在web3 js中的未定义

EN

import React, {Component} from 'react';
import '../node_modules/bootstrap/dist/css/bootstrap.min.css';
import web3 from './web3.js';
import voting from './voting.js';
import './App.css';

class App extends Component {
  constructor(){
    super();
    this.state = {
     account: '',

  }
}

componentDidMount = async () =>  {        
    const accounts = await web3.eth.getAccounts();               
    console.log(accounts[0]);          
}

import Web3 from 'web3';
const web3 = new Web3(window.web3.currentProvider);
export default web3;

import web3 from './web3';

const address = "0xd278D619eBca4583bc9923F0ac0043525CD08bA8";

const abi = [.......];

export default web3.eth.contract(abi, address);