使用web3.js收发ETH或ERC20Token

    以太坊的转账分主要分为为ETH转账、ERC20转账这2种，其转账流程，如图(1)所示：

图(1) 以太坊转账流程图

1、初始化原始交易单rawTx{}

    ETH和ERC20这2种类型的代币，主要区别，发生在第3步"初始化原始的交易单rawTx{}"时，设置to字段和value字段有差别，如下表所示：

rawTx	ETH	ERC20	说明
from	fromAddress	fromAddress	Token发送人
nonce	web3.utils.toHex(nonceNum)	web3.utils.toHex(nonceNum)	交易的nonce值
gasLimit	web3.utils.toHex(8000000)	web3.utils.toHex(8000000)	区块的gas个数上限
gasPrice	web3.utils.toHex(10e9)	web3.utils.toHex(10e9)	单步计算所需的gas
to	toAddress	contractAddress	当币种为ETH时，填Token接收人；当币种为ERC20时，填合约地址
value	web3.utils.toHex(sendNum)	“0x0”	当币种为ETH时，填ETH的个数； 当币种为ERC20时，置空
data	contractObj.methods.transfer(toAddress, sendNum).encodeABI()	contractObj.methods.transfer(toAddress, sendNum).encodeABI()	发送Token，并编码
chainId	0x04	0x04	网段为Rinkeby

    初始化rawTx{}的代码对比如下：

图(2) 初始化rawTx{}

2、查询余额

2.1 查询账户的ETH余额

function getEthBalance(fromAddress, bookmark) {
    web3.eth.getBalance(fromAddress).then(
        function (wei) {
            balance = web3.utils.fromWei(wei, 'ether')
            console.log(bookmark + balance);
        }
    )
}

2.2 查询账户的某种ERC20余额

function getERC20Balance(fromAddress,contractObj,bookmark) {
    contractObj.methods.balanceOf(fromAddress).call().then(
        function (wei) {
            balance = web3.utils.fromWei(wei, 'ether');
            console.log(bookmark + balance);
    });
}

    对比如下:

图(3) 获取ETH或者ERC20的余额

3、使用web3.js来发送Token

3.1 创建sendToken工程

    3.1.1 创建一个文件夹名称为sendToken

mkdir sendToken

    3.1.2 用npm和truffle初始化该该工程

cd sendToken
npm init -y
truffle init

    3.1.3 修改sendToken\package.json文件，改成如下：
    //package.json

{
  "name": "sendToken",
  "version": "1.0.0",
  "description": "",
  "main": "truffle-config.js",
  "directories": {
    "test": "test"
  },
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@openzeppelin/contracts": "^2.5.0",
    "@truffle/hdwallet-provider": "^1.1.1",
    "bignumber": "^1.1.0",
    "bignumber.js": "^8.1.1",
    "chai": "^4.2.0",
    "chai-as-promised": "^7.1.1",
    "eslint": "^5.15.0",
    "ethereumjs-tx": "^1.3.7",
    "request": "^2.88.2",
    "web3": "^1.3.0"
  },
  "devDependencies": {
    "@babel/core": "^7.12.3",
    "@babel/preset-env": "^7.12.1"
  }
}

    3.1.4 安装依赖包

npm install

    3.1.5 新建一个文件夹名称为myabi，然后在sendToken\myabi\目录下，新建一个ZTA_abi.json文件，该文件存放ZTA合约的abi

    3.1.6 新建一个文件夹名称为projectConfig，然后在sendToken\projectConfig\目下，如下几个文件:
    net.infuraKey 存放Infura节点的Key值
    net.mnemonic 存放账户的助记词
    net.prikey 存放账户的私钥

    3.1.7 整个工程的目录结构如下:

图(3) sendToken的目录结构

3.2 发送ETH

    将如下代码保存到sendToken\test\1.sendEth.js里，该代码是发送0.02ETH
    //1.sendEth.js

var Tx = require('ethereumjs-tx');
var Web3 = require('web3')

var fs = require('fs');
const infuraKey = fs.readFileSync("./projectConfig/net.infuraKey").toString().trim();
var web3 = new Web3(new Web3.providers.HttpProvider(`https://rinkeby.infura.io/v3/` + infuraKey))

// web3 version 
console.log(`web3 version: ${web3.version}`)


function getEthBalance(fromAddress, bookmark) {
    web3.eth.getBalance(fromAddress).then(
        function (wei) {
            balance = web3.utils.fromWei(wei, 'ether')
            console.log(bookmark + balance);
        }
    )
}

function getPriKey(prikeyPath) {
    const privKeyFile = fs.readFileSync(prikeyPath).toString().trim();
    const privKey = new Buffer.from(privKeyFile, 'hex');    
    return privKey
}

function getEthRawTx(fromAddress,toAddress,contractObj,sendNum,nonceNum, privKey) {
    //raw Tx
    var rawTransaction = {
        "from": fromAddress,
        "nonce": web3.utils.toHex(nonceNum),
        "gasLimit": web3.utils.toHex(8000000),
        "gasPrice": web3.utils.toHex(10e9),
        "to": toAddress,
        "value": web3.utils.toHex(sendNum),
        "data": contractObj.methods.transfer(toAddress, sendNum).encodeABI(),
        "chainId": 0x04 //4:Rinkeby, 3:Ropsten, 1:mainnet
    };

    var tx = new Tx(rawTransaction);
    tx.sign(privKey);
    var serializedTx = tx.serialize();
    return serializedTx;
}

async function signTransaction(fromAddress,toAddress,contractObj,sendNum,nonceNum, privKey) {
    var serializedTx = getEthRawTx(fromAddress,toAddress,contractObj,sendNum,nonceNum, privKey)

    // Comment out these three lines if you don't really want to send the TX right now
    console.log(`Attempting to send signed tx:  ${serializedTx.toString('hex')}`);
    var receipt = await web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'));
    console.log(`Receipt info:  ${JSON.stringify(receipt, null, '\t')}`);
}

function sleep(delay) {
    return new Promise(reslove => {
      setTimeout(reslove, delay)
    })
}

//an async function 
const sendEth = async () => {

    //the number of sended token
    //20 milli = 0.02 ether
    var transferAmount = web3.utils.toWei('20', 'milli');

    var myAddress = "0x1d75...a5f";
    var destAddress = "0x8a40....23fb";

    // get the nonce
    var nonceCnt = await web3.eth.getTransactionCount(myAddress);
    console.log(`num transactions so far: ${nonceCnt}`);


    var abiArray = JSON.parse(fs.readFileSync("./myabi/ZTA_abi.json"));
    var contractAddress = "0xAc194f047E43Ee0Ee10026C0B7AAA66489a0Ec45";
    var contract = new web3.eth.Contract(abiArray, contractAddress, { from: myAddress });

    // begin eth numbers of myAddress
    await getEthBalance(myAddress, "Balance before send: ");

    const privkey = getPriKey("./projectConfig/net.prikey")
    await signTransaction(myAddress,destAddress,contract,transferAmount,nonceCnt, privkey)

    sleep(100) //100ms

    // end eth numbers of myAddress
    await getEthBalance(myAddress, "Balance After send: ");
}

sendEth();

    执行该nodejs脚本

node test\1.sendETH.js

    效果如下：

图(4) 发送0.02个ETH Token

    也可以直接调用web3来发送ETH，即不调用合约来发送ETH，代码如下：
    //3.sendETHv2.js

var Tx = require('ethereumjs-tx');
var Web3 = require('web3')

var fs = require('fs');
const infuraKey = fs.readFileSync("./projectConfig/net.infuraKey").toString().trim();
var web3 = new Web3(new Web3.providers.HttpProvider(`https://rinkeby.infura.io/v3/` + infuraKey))

// web3 version 
console.log(`web3 version: ${web3.version}`)


function getEthBalance(fromAddress, bookmark) {
    web3.eth.getBalance(fromAddress).then(
        function (wei) {
            balance = web3.utils.fromWei(wei, 'ether')
            console.log(bookmark + balance);
    });
}

function getPriKey(prikeyPath) {
    const privKeyFile = fs.readFileSync(prikeyPath).toString().trim();
    const privKey = new Buffer.from(privKeyFile, 'hex');    
    return privKey
}

function getEthRawTx(fromAddress,toAddress,sendNum,nonceNum, privKey) {
    //raw Tx
    var rawTransaction = {
        "from": fromAddress,
        "nonce": web3.utils.toHex(nonceNum),
        "gasLimit": web3.utils.toHex(8000000),
        "gasPrice": web3.utils.toHex(10e9),
        "to": toAddress,
        "value": web3.utils.toHex(sendNum),
        "data": '',
        "chainId": 0x04 //4:Rinkeby, 3:Ropsten, 1:mainnet
    };

    var tx = new Tx(rawTransaction);
    tx.sign(privKey);
    var serializedTx = tx.serialize();
    return serializedTx;
}

async function signTransaction(fromAddress,toAddress,sendNum,nonceNum, privKey) {
    var serializedTx = getEthRawTx(fromAddress,toAddress,sendNum,nonceNum, privKey)

    // Comment out these three lines if you don't really want to send the TX right now
    console.log(`Attempting to send signed tx:  ${serializedTx.toString('hex')}`);
    var receipt = await web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'));
    console.log(`Receipt info:  ${JSON.stringify(receipt, null, '\t')}`);
}

function sleep(delay) {
    return new Promise(reslove => {
      setTimeout(reslove, delay)
    })
}

//an async function 
const sendEth = async () => {

    //the number of sended token
    //20 milli = 0.02 ether
    var transferAmount = web3.utils.toWei('20', 'milli');

    var myAddress = "0x1d75...a5f";
    var destAddress = "0x8a40....23fb";

    // get the nonce
    var nonceCnt = await web3.eth.getTransactionCount(myAddress);
    console.log(`num transactions so far: ${nonceCnt}`);

    // begin eth numbers of myAddress
    await getEthBalance(myAddress, "Balance before send: ");

    const privkey = getPriKey("./projectConfig/net.prikey")
    await signTransaction(myAddress,destAddress,transferAmount,nonceCnt, privkey)

    sleep(100) //100ms

    // end eth numbers of myAddress
    await getEthBalance(myAddress, "Balance After send: ");
}

sendEth();

3.3 发送ERC20

    将如下代码保存到sendToken\test\2.sendERC20.js里，该代码是发送0.02 ZTA
    //2.sendERC20.js

var Tx = require('ethereumjs-tx');
var Web3 = require('web3')

var fs = require('fs');
const infuraKey = fs.readFileSync("./projectConfig/net.infuraKey").toString().trim();
var web3 = new Web3(new Web3.providers.HttpProvider(`https://rinkeby.infura.io/v3/` + infuraKey))

// web3 version 
console.log(`web3 version: ${web3.version}`)

function getERC20Balance(fromAddress,contractObj,bookmark) {
    contractObj.methods.balanceOf(fromAddress).call().then(
        function (wei) {
            balance = web3.utils.fromWei(wei, 'ether');
            console.log(bookmark + balance);
    });
}

function getPriKey(prikeyPath) {
    const privKeyFile = fs.readFileSync(prikeyPath).toString().trim();
    const privKey = new Buffer.from(privKeyFile, 'hex');    
    return privKey
}


function getERC20RawTx(fromAddress,toAddress,contractAddress,contractObj,sendNum,nonceNum, privKey) {
    //raw Tx
    var rawTransaction = {
        "from": fromAddress,
        "nonce": web3.utils.toHex(nonceNum),
        "gasLimit": web3.utils.toHex(8000000),
        "gasPrice": web3.utils.toHex(10e9),
        "to": contractAddress,
        "value": "0x0",
        "data": contractObj.methods.transfer(toAddress, sendNum).encodeABI(),
        "chainId": 0x04 //4:Rinkeby, 3:Ropsten, 1:mainnet
    };

    var tx = new Tx(rawTransaction);
    tx.sign(privKey);
    var serializedTx = tx.serialize();
    return serializedTx;
}

async function signERC20Transaction(fromAddress,toAddress,contractAddress,contractObj,sendNum,nonceNum, privKey) {
    var serializedTx = getERC20RawTx(fromAddress,toAddress,contractAddress,contractObj,sendNum,nonceNum, privKey)

    // Comment out these three lines if you don't really want to send the TX right now
    console.log(`Attempting to send signed tx:  ${serializedTx.toString('hex')}`);
    var receipt = await web3.eth.sendSignedTransaction('0x' + serializedTx.toString('hex'));
    console.log(`Receipt info:  ${JSON.stringify(receipt, null, '\t')}`);
}

function sleep(delay) {
    return new Promise(reslove => {
      setTimeout(reslove, delay)
    })
}

//an async function 
const sendERC20 = async () => {

    //the number of sended token
    //20 milli = 0.02 ether
    var transferAmount = web3.utils.toWei('20', 'milli');

    var myAddress = "0x1d75...a5f";
    var destAddress = "0x8a40....23fb";

    // get the nonce
    var nonceCnt = await web3.eth.getTransactionCount(myAddress);
    console.log(`num transactions so far: ${nonceCnt}`);

    var abiArray = JSON.parse(fs.readFileSync("./myabi/ZTA_abi.json"));
    var contractAddress = "0xAc194f047E43Ee0Ee10026C0B7AAA66489a0Ec45";
    var contract = new web3.eth.Contract(abiArray, contractAddress, { from: myAddress });

    // begin token numbers
    await getERC20Balance(myAddress,contract,"Balance before send: ");

    const privkey = getPriKey("./projectConfig/net.prikey")
    await signERC20Transaction(myAddress,destAddress,contractAddress,contract,transferAmount,nonceCnt, privkey)

    sleep(100)  //100ms

    // end token numbers
    await getERC20Balance(myAddress,contract,"Balance before send: ");
}

sendERC20();

    执行该nodejs脚本

node test\2.sendERC20.js

    效果如下：

图(5) 发送0.02 ZTA Token