web3 编译部署调用合约

//导入solc 编译器
let solc = require('solc')
let fs = require('fs')
//读取合约
let sourceCode = fs.readFileSync('./contracts/SimpleStorage.sol','utf-8')

//var input = 'contract x { function g() {} }'
// Setting 1 as second paramateractivates the optimiser
//编译合约
let output = solc.compile(sourceCode, 1)
module.exports = output['contracts'][':SimpleStorage']

部署合约

let {bytecode, interface} = require('./01-complie')
//console.log(bytecode)
//console.log(interface) 

// 1.引入web3
let Web3 = require('web3')
// 2.new 一个web3实例
let web3 = new Web3()
// 3.设置网络
let isConnect = web3.setProvider('http://localhost:7545')

const account = '0x975938478Fa7359567b84E9c9ccc20b2aac23066'

//console.log(isConnect)
//console.log("version:", web3.version)
//console.log(web3.eth.currentProvider)

// 1. 拼接合约数据 interface
let contract = new web3.eth.Contract(JSON.parse(interface))
// 2. 拼接bytecode
contract.deploy({
    data: bytecode,//合约bytecode
    arguments: ['HelloWorld'] //给构造函数传递参数,使用数组
}).send({
    from: account,
    gas: '3000000',
    //gasPrice: '1',
}).then(instance =>{
    console.log('address :',instance.options.address)
});
// 3. 合约部署

获取合约实例

//获取 合约实例，导出合约实例
let {bytecode, interface} = require('./01-complie')

// 1.引入web3
let Web3 = require('web3')
// 2.new 一个web3实例
let web3 = new Web3()
// 3.设置网络
let isConnect = web3.setProvider('http://localhost:7545')
// 合约的abi
let abi = [{"constant":false,"inputs":[{"name":"message","type":"string"}],"name":"setMessage","outputs":[],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[],"name":"getMessage","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"str","type":"string"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]
//合约地址
let address = '0x7f61E1A3970777C3C25DA410fD6E2c3CfCFB953a';
//此处abi 已经是json对象了不需要进行parse动作
let contractInstance = new web3.eth.Contract(abi,address);

//console.log('address',contractInstance.options.address);
module.exports = contractInstance;

调用合约

//1 .导入合约实例
let instance = require('./03-instance');
const from = '0x4E4c6a3655A5863089f9341ff61D3d8BeE00384a';

//异步调用,返回值是一个promise
//2。读取数据
/*
instance.methods.getMessage().call().then(data => {
    console.log('data: ', data);
    //3.写入数据
    instance.methods.setMessage('Hello JackLuo').send({
        from: from,
        value: 0
    }).then(res => {
        //4.读取数据
        console.log('res :', res)
        instance.methods.getMessage().call().then(data => {
            console.log('data2: ', data);
        })
    })
});
*/

// web3与区块链交互的返回值都是promise,可以直接使用async/await
let test = async () => {
    try {
        let v1 = await instance.methods.getMessage().call()
        console.log('v1:', v1)
        let res = await instance.methods.setMessage('Hello Jackluo').send({
            from: from,
            value: 0
        });
        console.log('res:', res)
        let v2 = await instance.methods.getMessage().call()
        console.log('v2:', v2)
    } catch (e) {
        console.log(e)
    }
};

test();