注意：请在服务端运行！！！

结构代码

<div id="app"><h5>imToken</h5><p>当前环境:<span class="env">null</span></p><button class="Web3Button">Web3js获取信息</button><h2>Account(账户): <span class="showAccount1"></span></h2><h2>Balance(ETH): <span class="showBalance1"></span></h2><p>内容:<span class="cont">null</span></p>
</div>
<script src="./node_modules/web3/dist/web3.min.js"></script>

逻辑代码

// 获取dom元素
const env = document.querySelector(".env");
const cont = document.querySelector(".cont");const ethereumButton1 = document.querySelector('.Web3Button');
const showAccount1 = document.querySelector('.showAccount1');
const showBalance1 = document.querySelector('.showBalance1');// Web3浏览器检测
if (typeof window.ethereum !== 'undefined') {console.log('MetaMask is installed!');
}// 实例化web3
window.web3 = new Web3(ethereum);
var web3 = window.web3;// 可以通过 !!window.imToken 或者 window.ethereum.isImToken 来检测当前浏览器环境是否是 imToken DApp browser, true 表示当前是 imToken 环境
let envs = null;
!!window.imToken ? envs = '当前是 imToken 环境' : envs = '当前不是 imToken 环境';
console.log(envs);
env.innerHTML = envs;// 获取账户信息
ethereumButton1.addEventListener('click', () => {getAccount1();
});
async function getAccount1() {if (!!window.imToken) {// 授权获取账户var accounts = await web3.eth.getAccounts();// web3.eth.getAccounts().then((e)=>{console.log(e)})// 取第一个账户var myAccount = accounts[0];console.log(myAccount, typeof myAccount, 1);// 返回指定地址账户的余额var balance = await web3.eth.getBalance(myAccount);let eth =  web3.utils.fromWei(balance, 'ether');console.log(balance,eth, typeof balance, 2)showAccount1.innerHTML = myAccount;showBalance1.innerHTML = `wei:${balance}, ether:${eth}`;}else{showAccount1.innerHTML = '非 imToken 环境';showBalance1.innerHTML = '非 imToken 环境';}
}