如何在Javascript函数中通过Web3返回交易哈希值？

Question

我正在关注How to authenticate and send contract method using web3.js 1.0的第二个答案

我希望在智能合约中执行一种方法。我按照下面的代码。我正在尝试获取事务哈希值（“哈希”）并在我的js函数中返回该值。我该怎么办？

到目前为止，我只能通过console.log（hash）在控制台上看到事务哈希，而我尝试输出哈希值或返回值的任何尝试均失败。我得到“未定义”或空值。

'use strict';
const Web3 = require('web3');

const wsAddress = 'wss://rinkeby.infura.io/ws';
const contractJson = '(taken from solc or remix online compiler)';
const privateKey = '0xOOOX';
const contractAddress = '0xOOOX';
const walletAddress = '0xOOOX';

const webSocketProvider = new Web3.providers.WebsocketProvider(wsAddress);
const web3 = new Web3(new Web3.providers.WebsocketProvider(webSocketProvider));
const contract = new web3.eth.Contract(
  JSON.parse(contractJson),
  contractAddress
);
// change this to whatever contract method you are trying to call, E.G. SimpleStore("Hello World")
const query = contract.methods.SimpleStore('Hello World');
const encodedABI = query.encodeABI();
const tx = {
  from: walletAddress,
  to: contractAddress,
  gas: 2000000,
  data: encodedABI,
};

const account = web3.eth.accounts.privateKeyToAccount(privateKey);
console.log(account);
web3.eth.getBalance(walletAddress).then(console.log);

web3.eth.accounts.signTransaction(tx, privateKey).then(signed => {
  const tran = web3.eth
    .sendSignedTransaction(signed.rawTransaction)
    .on('confirmation', (confirmationNumber, receipt) => {
      console.log('=> confirmation: ' + confirmationNumber);
    })
    .on('transactionHash', hash => {
      console.log('=> hash');
      console.log(hash);
    })
    .on('receipt', receipt => {
      console.log('=> reciept');
      console.log(receipt);
    })
    .on('error', console.error);
});