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智能合约开发

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代码地址 ​

dlsq

以太坊客户端 ​

EVM ​

智能合约的运行环境，是一个虚拟机

以太坊客户端 ​

  1. 定义：也就是 EVM 的载体，也就是区块链网络中的节点的程序，只要符合网络规范，任何语言都可以实现客户端
  2. 常见的客户端：Geth(Go 实现)、OpenEthereum(Rust 实现)，通过 RPC 提供服务

账户 ​

本质都是一个 20 个字节表示的地址

  1. 外部账户（EOA）：由私钥控制（比如用户的地址）

  2. 合约账户：代码控制（比如合约代码的部署地址）

注意：交易只能从外部账号发出，合约只能被动执行。合约之间的交互称为消息，所有的 gas 都由外部账号支付

Gas ​

GAS 是一个工作量单位，复杂度越大，所需 gas 越多。费用=gas 数量*gas 单价（以太币计价 gwei）

单位 ​

  • 最小单位：Wei
  • 10^9 Wei = 1 Gwei
  • 10^12 Wei = 1 Szabo
  • 10^15 Wei = 1 Finney
  • 10^18 Wei = 1 Ether

网络 ​

  1. 主网（价值网络）
  2. 测试网
  3. 开发模拟网（本地环境，一般就是借助工具起虚拟机）

合约的编译、部署、测试 ​

1. Remix ​

链接

在contracts里添加Counter.sol

solidity
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
    }
}
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
    }
}

编辑器左侧面板有文件夹区域、搜索区域、编译区域、部署区域。

编译区域可选编译器版本。

部署区域可选部署链，成功后会显示部署地址。部署合约也是一笔交易，需要在钱包确认，也需要gas费。部署成功后会显示交互面板，橙色是触发交易，蓝色仅读取。点击橙色触发交易，需要钱包确认，需要gas费。点击蓝色读就不需要。

实际操作：environment 选择 injected web3，这里连接 metamusk 钱包，钱包啥网络，就是啥网络。推荐用 goerli（eth 测试网）,去goerli faucet申请一点测试币即可。部署前会连接钱包，然后就是用账号部署上去,部署完后可以去测试链查状态。

部署成功后，点两次橙色触发交易，再点蓝色可以读到此时counter值的状态，控制台打印：

shell
{
	"0": "uint256: 2"
}
{
	"0": "uint256: 2"
}

注意 remix 中的 environment 如果是默认的，那就是虚拟网络，在区块链浏览器是查不到的，而且不需要钱包验证，也不需要gas费

2. Truffle ​

Truffle:编译、部署、测试合约的一整套开发工具

ganache是开发区块链，提供本地模拟的链上环境

官方文档

中文文档

我的代码

shell
Truffle 安装  npm install -g truffle
创建工程 truffle init或者truffle unbox metacoin(我用的第二个，相当于使用metacoin这个模版，注意需要手动mkdir一个folder，再在里面执行创建，注意配置proxy)
Truffle 安装  npm install -g truffle
创建工程 truffle init或者truffle unbox metacoin(我用的第二个，相当于使用metacoin这个模版，注意需要手动mkdir一个folder，再在里面执行创建，注意配置proxy)

truffle工程包含

  • contracts:智能合约目录
  • migrations:迁移文件，用来指示如何部署智能合约
  • test:智能合约测试用例文件夹
  • truffle-config.js:配置文件，配置truffle连接的网络及编译选项
  • build:编译结果目录

改造下folder

  1. 删除contracts、migrations、test下的文件

  2. contracts里添加Counter.sol

    solidity
    // SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
    }
}
    // SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
    }
}

合约编译 ​

shell
//使用命令
truffle compile
//使用命令
truffle compile

在那之前需要配置truffle-config.js，不配置就是默认的0.5.16版本

js
module.exports={
  compilers:{
    solc:{
      version:"0.8.9"
    }
  }
}
module.exports={
  compilers:{
    solc:{
      version:"0.8.9"
    }
  }
}

编译完成会输出在build目录,同时也会在命令行输出编译使用的编译器

shell
> Compiled successfully using:
   - solc: 0.8.9+commit.e5eed63a.Emscripten.clang
> Compiled successfully using:
   - solc: 0.8.9+commit.e5eed63a.Emscripten.clang

编译结果是json（与合约一一对应），里面abi是和前端交互的，bytecode就是最后部署在链上的东西

接下来是合约的部署 ​

shell
//使用命令
truffle migrate
truffle migrate --network networkname //可以在后面加network参数和network名字，部署到指定network
//使用命令
truffle migrate
truffle migrate --network networkname //可以在后面加network参数和network名字，部署到指定network

在那之前，需要先写好配置文件

  1. 编写部署脚本

    migrations里添加1_counter.js

    js
    const Counter = artifacts.require("Counter");

module.exports = function (deployer) {
  deployer.deploy(Counter);
};
    const Counter = artifacts.require("Counter");

module.exports = function (deployer) {
  deployer.deploy(Counter);
};

  2. 部署到本地节点（我没有搞）

    1. 先启动一个服务模拟链上环境ganache-cli -p 7545(ganache是开发区块链，提供本地模拟的链上环境)

    2. 然后添加dev的network

      js
      //truffle-config.js development网络配置

module.exports={
  networks:{
    development:{
      host:"127.0.0.1",
      port:7545,
   		network_id:"*"
    }
  }
}
      //truffle-config.js development网络配置

module.exports={
  networks:{
    development:{
      host:"127.0.0.1",
      port:7545,
   		network_id:"*"
    }
  }
}

    3. truffle migrate — network development部署，本地部署，不需要验证和gas费

  3. 部署到链上

    1. 需要部署到链上的节点，所以先去infura.io创建一个project，然后copy project id（选择endpoints是goerli）

    2. 当前目录新建两个隐藏文件，.api_key和.mnemonic，.gitignore要添加这两项，分别存储上一步的id和你的钱包账户助记词（主要为了防止外泄）

    3. 初始化npm ，添加truffle-hdwallet-provider包

      shell
      npm init
npm i truffle-hdwallet-provider -s
.gitignore 添加node_modules
      npm init
npm i truffle-hdwallet-provider -s
.gitignore 添加node_modules

    4. config.js里的network里添加新的network goerli

      js
      const HDWalletProvider = require("truffle-hdwallet-provider");

const fs = require('fs');
const api_key = fs.readFileSync('.api_key').toString().trim();
const mnemonic = fs.readFileSync('.mnemonic').toString().trim();
module.exports = {
  networks: {
    goerli: {
      provider: () => {
        return new HDWalletProvider(mnemonic, 'https://goerli.infura.io/v3/' + api_key)
      },
      network_id: '5',
      gas: 4465030,
      gasPrice: 10000000000,
    },
  }
};
      const HDWalletProvider = require("truffle-hdwallet-provider");

const fs = require('fs');
const api_key = fs.readFileSync('.api_key').toString().trim();
const mnemonic = fs.readFileSync('.mnemonic').toString().trim();
module.exports = {
  networks: {
    goerli: {
      provider: () => {
        return new HDWalletProvider(mnemonic, 'https://goerli.infura.io/v3/' + api_key)
      },
      network_id: '5',
      gas: 4465030,
      gasPrice: 10000000000,
    },
  }
};

    5. 执行truffle migrate — network goerli部署到goerli，这里会消耗gas费，但没有metamusk弹窗确认的过程，因为我输入了助记词，他直接在钱包扣款了

      shell
      //命令行输出
Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.


Migrations dry-run (simulation)
===============================
> Network name:    'goerli-fork'
> Network id:      5
> Block gas limit: 30000000 (0x1c9c380)


1_counter.js
============

   Deploying 'Counter'
   -------------------
   > block number:        6818292
   > block timestamp:     1651505825
   > account:             0x736D76f4C2d4b4CCced0CCA92d3dF0F0e456F35D
   > balance:             0.04813429249775099
   > gas used:            135269 (0x21065)
   > gas price:           10 gwei
   > value sent:          0 ETH
   > total cost:          0.00135269 ETH

   -------------------------------------
   > Total cost:          0.00135269 ETH

Summary
=======
> Total deployments:   1
> Final cost:          0.00135269 ETH




Starting migrations...
======================
> Network name:    'goerli'
> Network id:      5
> Block gas limit: 29970705 (0x1c95111)


1_counter.js
============

   Deploying 'Counter'
   -------------------
   > transaction hash:    0x376710e125c35233b468bd232444acc2239c38e837aeecf9ef9de6762715eca8
   > Blocks: 0            Seconds: 5
   > contract address:    0xAc8dC14e7aC85556Bcc22c052FbB5Bc05D4E77D8
   > block number:        6818298
   > block timestamp:     1651505843
   > account:             0x736D76f4C2d4b4CCced0CCA92d3dF0F0e456F35D
   > balance:             0.04813429249775099
   > gas used:            135269 (0x21065)
   > gas price:           10 gwei
   > value sent:          0 ETH
   > total cost:          0.00135269 ETH

   > Saving artifacts
   -------------------------------------
   > Total cost:          0.00135269 ETH

Summary
=======
> Total deployments:   1
> Final cost:          0.00135269 ETH
      //命令行输出
Compiling your contracts...
===========================
> Everything is up to date, there is nothing to compile.


Migrations dry-run (simulation)
===============================
> Network name:    'goerli-fork'
> Network id:      5
> Block gas limit: 30000000 (0x1c9c380)


1_counter.js
============

   Deploying 'Counter'
   -------------------
   > block number:        6818292
   > block timestamp:     1651505825
   > account:             0x736D76f4C2d4b4CCced0CCA92d3dF0F0e456F35D
   > balance:             0.04813429249775099
   > gas used:            135269 (0x21065)
   > gas price:           10 gwei
   > value sent:          0 ETH
   > total cost:          0.00135269 ETH

   -------------------------------------
   > Total cost:          0.00135269 ETH

Summary
=======
> Total deployments:   1
> Final cost:          0.00135269 ETH




Starting migrations...
======================
> Network name:    'goerli'
> Network id:      5
> Block gas limit: 29970705 (0x1c95111)


1_counter.js
============

   Deploying 'Counter'
   -------------------
   > transaction hash:    0x376710e125c35233b468bd232444acc2239c38e837aeecf9ef9de6762715eca8
   > Blocks: 0            Seconds: 5
   > contract address:    0xAc8dC14e7aC85556Bcc22c052FbB5Bc05D4E77D8
   > block number:        6818298
   > block timestamp:     1651505843
   > account:             0x736D76f4C2d4b4CCced0CCA92d3dF0F0e456F35D
   > balance:             0.04813429249775099
   > gas used:            135269 (0x21065)
   > gas price:           10 gwei
   > value sent:          0 ETH
   > total cost:          0.00135269 ETH

   > Saving artifacts
   -------------------------------------
   > Total cost:          0.00135269 ETH

Summary
=======
> Total deployments:   1
> Final cost:          0.00135269 ETH

补充内容 ​

  1. Truffle console使用（可以直接在控制台调用合约）

    先把合约部署到development

    truffle console --network development开启调用模式

  2. truffle-min.sh(压缩artifacts文件)

    我们compile后，是会在build里输出一个json，但是这个json很大，所以可以借助这个脚本来对这个json进行压缩，可以从几千行压缩到几十行，然后我们后续的开发有引用这个json的需求的时候，就可以引入这个压缩的json

3. Hardhat ​

Hardhat:编译、部署、测试和调试以太坊应用的开发环境，围绕task（任务）和plugins（插件）概念设计

在命令行运行Hardhat时，都是在运行任务，例如：npx hardhat compile就是运行compile任务

Hardhat node:开发区块链，提供本地模拟的链上环境

官方文档,中文文档

参考代码

我的代码

创建工程 ​

shell
mkdir hardhat-demo //创建一个folder
cd hardhat-demo
npm init //初始化npm
npm i -s hardhat //当前目录下安装hardhat
npx hardhat //在当前目录下创建项目,可以选basic-sample(注意，这一步要开启shell proxy)
mkdir hardhat-demo //创建一个folder
cd hardhat-demo
npm init //初始化npm
npm i -s hardhat //当前目录下安装hardhat
npx hardhat //在当前目录下创建项目,可以选basic-sample(注意，这一步要开启shell proxy)

contracts里新建Counter.sol，添加一下内容

solidity
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;
import "hardhat/console.sol";

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
        console.log("curr counter:",counter);
    }
    function add(uint x) public{
        counter=counter+x;
    }
}
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;
import "hardhat/console.sol";

contract Counter{
    uint public counter;
    constructor(){
        counter = 0;

    }
    function count() public{
        counter+=1;
        console.log("curr counter:",counter);
    }
    function add(uint x) public{
        counter=counter+x;
    }
}

合约编译 ​

js
//先修改hardhat.config.js，设置编译器版本
module.exports={
  Solidity:"0.8.9"
}
//然后命令行输入
npx hardhat compile
//先修改hardhat.config.js，设置编译器版本
module.exports={
  Solidity:"0.8.9"
}
//然后命令行输入
npx hardhat compile

部署 ​

  1. 编写部署脚本

    js
    //scripts/deploy_counter.js
const hre = require("hardhat");
async function main() {
  //await hre.run('compile');
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(); //deploy里的括号可以传参，具体看合约里的construtor有没有参数而定

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);
}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });
    //scripts/deploy_counter.js
const hre = require("hardhat");
async function main() {
  //await hre.run('compile');
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(); //deploy里的括号可以传参，具体看合约里的construtor有没有参数而定

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);
}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

    如果想要一次部署多个合约，比如这里有counter和greeter合约，那么可以这么写

    js
    //scripts/deploy.js

const { ethers } = require("hardhat");

async function main() {
  const [deployer] = await ethers.getSigners();
  console.log('Deploying contracts with the account: ' + deployer.address);

  // Deploy Greeter
  const Greeter = await ethers.getContractFactory("Greeter");
  const greeter = await Greeter.deploy("Hello, Hardhat!");


  // Deploy Counter
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy();
  
  // console.log
	console.log("Greeter deployed to:", greeter.address);
  console.log("Counter deployed to:", counter.address);

}

main()
    .then(() => process.exit())
    .catch(error => {
        console.error(error);
        process.exit(1);
})
    //scripts/deploy.js

const { ethers } = require("hardhat");

async function main() {
  const [deployer] = await ethers.getSigners();
  console.log('Deploying contracts with the account: ' + deployer.address);

  // Deploy Greeter
  const Greeter = await ethers.getContractFactory("Greeter");
  const greeter = await Greeter.deploy("Hello, Hardhat!");


  // Deploy Counter
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy();
  
  // console.log
	console.log("Greeter deployed to:", greeter.address);
  console.log("Counter deployed to:", counter.address);

}

main()
    .then(() => process.exit())
    .catch(error => {
        console.error(error);
        process.exit(1);
})

  2. 部署到本地网络

    先启动一个本地网络npx hardhat node,然后再根据端口值来修改hardhat.config.js，增加以下内容

    js
    //hardhat.config.js
module.exports={
  networks:{
    development:{
      url:"http://127.0.0.1:8545",
      chainId:31337
    }
  }
}
    //hardhat.config.js
module.exports={
  networks:{
    development:{
      url:"http://127.0.0.1:8545",
      chainId:31337
    }
  }
}

    执行部署npx hardhat run scripts/deploy_xxx.js [--network 网络]，而这里的话，就是执行npx hardhat run scripts/deploy_counter.js --network development

  3. 部署到链上

    需要部署到链上的节点，所以先去infura.io创建一个project，然后copy project id（选择endpoints是goerli）

    本地添加.api_key和.mnemonic，.gitignore添加过滤这两项，然后修改hardhat.config.js,增加以下内容

    js
    //hardhat.config.js
const fs = require('fs');
const api_key = fs.readFileSync('.api_key').toString().trim();
const mnemonic = fs.readFileSync('.mnemonic').toString().trim();
module.exports={
  networks:{
    goerli:{
      url:`https://goerli.infura.io/v3/${api_key}`,
      accounts:{
        mnemonic:mnemonic,
      }
    }
  }
}
    //hardhat.config.js
const fs = require('fs');
const api_key = fs.readFileSync('.api_key').toString().trim();
const mnemonic = fs.readFileSync('.mnemonic').toString().trim();
module.exports={
  networks:{
    goerli:{
      url:`https://goerli.infura.io/v3/${api_key}`,
      accounts:{
        mnemonic:mnemonic,
      }
    }
  }
}

​ 执行部署npx hardhat run scripts/deploy.js --network goerli

测试 ​

js
const {expect} = require("chai");
const {ethers} = require("hardhat");

describe("Counter", function () {
  it("counter should be 0 when init , be added 1 after count be called, be added x after add be called with x", async function () {
    const Counter = await ethers.getContractFactory("Counter");
    const counterInstance = await Counter.deploy();
    await counterInstance.deployed();
    expect(await counterInstance.counter()).to.equal(0);

    const setCountTx = await counterInstance.count();

    // wait until the transaction is mined
    await setCountTx.wait();

    expect(await counterInstance.counter()).to.equal(1);

    const addCountTx = await counterInstance.add(10);
    await addCountTx.wait();
    expect(await counterInstance.counter()).to.equal(11);
  });
});
const {expect} = require("chai");
const {ethers} = require("hardhat");

describe("Counter", function () {
  it("counter should be 0 when init , be added 1 after count be called, be added x after add be called with x", async function () {
    const Counter = await ethers.getContractFactory("Counter");
    const counterInstance = await Counter.deploy();
    await counterInstance.deployed();
    expect(await counterInstance.counter()).to.equal(0);

    const setCountTx = await counterInstance.count();

    // wait until the transaction is mined
    await setCountTx.wait();

    expect(await counterInstance.counter()).to.equal(1);

    const addCountTx = await counterInstance.add(10);
    await addCountTx.wait();
    expect(await counterInstance.counter()).to.equal(11);
  });
});

npx hardhat test执行测试

实战 ​

  1. 调试利器：console.log

    solidity
    import "hardhat/console.sol";

console.log(counter);
    import "hardhat/console.sol";

console.log(counter);

  2. 灵活参数部署，利用hardhat可以在代码中引用(这里值的是合约初始化的参数，也就是constructor需要的参数，比如Greeter合约，这里可以在部署脚本里传入参数，比如deploy_greeter.js所写。也可以用nodejs的方式，在命令行传入参数,然后在部署脚本里取出来)

    1. solidity
      // Counter.sol
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;
import "hardhat/console.sol";

contract Counter{
    uint public counter;
    constructor(uint _counter){
        counter = _counter;

    }
    function count() public{
        counter+=1;
        console.log("curr counter:",counter);
    }
    function add(uint x) public{
        counter=counter+x;
    }
}

// test_counter.js
const {expect} = require("chai");
const {ethers} = require("hardhat");

describe("Counter", function () {
  it("counter should be 0 when init , be added 1 after count be called, be added x after add be called with x", async function () {
    const Counter = await ethers.getContractFactory("Counter");
    const counterInstance = await Counter.deploy(0);
    await counterInstance.deployed();
    expect(await counterInstance.counter()).to.equal(0);

    const setCountTx = await counterInstance.count();

    // wait until the transaction is mined
    await setCountTx.wait();

    expect(await counterInstance.counter()).to.equal(1);

    const addCountTx = await counterInstance.add(10);
    await addCountTx.wait();
    expect(await counterInstance.counter()).to.equal(11);
  });
});

//deploy_counter.js
//其余相同，只需改下面这一句
 const counter = await Counter.deploy(0);
      // Counter.sol
// SPDX-License-Identifier:  MIT
pragma solidity ^0.8.0;
import "hardhat/console.sol";

contract Counter{
    uint public counter;
    constructor(uint _counter){
        counter = _counter;

    }
    function count() public{
        counter+=1;
        console.log("curr counter:",counter);
    }
    function add(uint x) public{
        counter=counter+x;
    }
}

// test_counter.js
const {expect} = require("chai");
const {ethers} = require("hardhat");

describe("Counter", function () {
  it("counter should be 0 when init , be added 1 after count be called, be added x after add be called with x", async function () {
    const Counter = await ethers.getContractFactory("Counter");
    const counterInstance = await Counter.deploy(0);
    await counterInstance.deployed();
    expect(await counterInstance.counter()).to.equal(0);

    const setCountTx = await counterInstance.count();

    // wait until the transaction is mined
    await setCountTx.wait();

    expect(await counterInstance.counter()).to.equal(1);

    const addCountTx = await counterInstance.add(10);
    await addCountTx.wait();
    expect(await counterInstance.counter()).to.equal(11);
  });
});

//deploy_counter.js
//其余相同，只需改下面这一句
 const counter = await Counter.deploy(0);

    2. 设置deploy脚本

      js
      const {ethers} = require("hardhat");

const params=process.argv;
const value=params[2];
console.log("Counter deploy with value:",value);
async function main() {
  //await hre.run('compile');
  const Counter = await ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(value);

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);

}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });
      const {ethers} = require("hardhat");

const params=process.argv;
const value=params[2];
console.log("Counter deploy with value:",value);
async function main() {
  //await hre.run('compile');
  const Counter = await ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(value);

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);

}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

    3. 执行node脚本,并传递参数

      需要两个命令，可以在命令行依次执行，也可以写成一个.sh，sh ./deploy_by_param.sh 执行这个.sh即可

      shell
      // ./deploy_by_param.sh
export HARDHAT_NETWORK='development' //设置network的值是development；这就是node执行hardhat脚本附着hardhat参数的方式+
node scripts/deploy_by_param.js 10 //在这里传入初始化参数是10
      // ./deploy_by_param.sh
export HARDHAT_NETWORK='development' //设置network的值是development；这就是node执行hardhat脚本附着hardhat参数的方式+
node scripts/deploy_by_param.js 10 //在这里传入初始化参数是10

  3. 代码扁平：npx hardhat flatten xxx.sol > xxx.sol

    本质的意义是，当一个合约的里面有import引用的时候，可以用这个命令把引用的代码和本身的代码放在一起，方便看，这里的话就是npx hardhat flatten contracts/Counter.sol >>Counter.sol

  4. 代码验证

    当合约部署在链上后，可以通过这个命令来对代码进行验证

    shell
    1.先安装 npm i hardhat-etherscan --dev
2.hardhat.config.js里添加require("@nomiclabs/hardhat-etherscan")
3.添加scankey,const scankey=`${scanKey}`; //因为调用etherscan的api，所以需要去他那里申请一个key, https://etherscan.io/,这个key最好也用隐藏文件，不要暴露出去
4.在配置里，networks的下面，添加同级项 etherscan:{apiKey:scankey}
5.命令行执行npx hardhat verify address --network xxx // address是合约的部署地址，xxx是要验证的网络
    1.先安装 npm i hardhat-etherscan --dev
2.hardhat.config.js里添加require("@nomiclabs/hardhat-etherscan")
3.添加scankey,const scankey=`${scanKey}`; //因为调用etherscan的api，所以需要去他那里申请一个key, https://etherscan.io/,这个key最好也用隐藏文件，不要暴露出去
4.在配置里，networks的下面，添加同级项 etherscan:{apiKey:scankey}
5.命令行执行npx hardhat verify address --network xxx // address是合约的部署地址，xxx是要验证的网络

  5. ABI导出

    当合约部署后，需要导出ABI供前端调用，默认的deploy就会导出一个总的json里面包括abi，不过比较大而已，这里是仅导出abi的json

    shell
    1.先安装 npm i hardhat-abi-exporter --dev
2.hardhat.config.js里添加require("hardhat-abi-exporter")
3.hardhat.config.js里配置下导出,新建./abi目录来存放
  abiExporter: {
    path: './abi',
    runOnCompile: true,
    clear: true,
    flat: true,
    spacing: 2,
    pretty: false,
  }
4.npx hardhat export-abi
    1.先安装 npm i hardhat-abi-exporter --dev
2.hardhat.config.js里添加require("hardhat-abi-exporter")
3.hardhat.config.js里配置下导出,新建./abi目录来存放
  abiExporter: {
    path: './abi',
    runOnCompile: true,
    clear: true,
    flat: true,
    spacing: 2,
    pretty: false,
  }
4.npx hardhat export-abi

  6. 自定义Task

    在hardhat.config.js里可以写task,然后通过npx hardhat taskName完成一些想要做的事，也可以在task文件夹里写，然后在hardhat.config.js用require引入

    js
    task("accounts","Prints the list of accounts",async(taskArgs,hre)=>{
  const accounts =await hre.ethers.getSigners();
  for(const account of accounts){
    console.log(account.address)
  }
})

//命令行 npx hardhat accounts执行
    task("accounts","Prints the list of accounts",async(taskArgs,hre)=>{
  const accounts =await hre.ethers.getSigners();
  for(const account of accounts){
    console.log(account.address)
  }
})

//命令行 npx hardhat accounts执行

  7. 书写脚本去调用合约，实现前端与合约的交互

    1. 前端想要调用合约，那就得知道合约的地址和abi，之前有用npm处理了abi的单独导出，但是并没有处理合约的地址，所以这里我们改造下deploy脚本，让它自动保存地址和abi到一个data的目录下

      js
      // scripts/deploy_counter.js
const hre = require("hardhat");
async function main() {
  //await hre.run('compile');
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(0);

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);
  saveFrontendFiles(counter);
}

function saveFrontendFiles(counter) {
  const fs = require("fs");
  const contractsDir = "./data";

  if (!fs.existsSync(contractsDir)) {
    fs.mkdirSync(contractsDir);
  }

  fs.writeFileSync(
    contractsDir + "/contract-address.json",
    JSON.stringify({
      Counter: counter.address
    }, undefined, 2)
  );

  const CounterArtifact = artifacts.readArtifactSync("Counter");

  fs.writeFileSync(
    contractsDir + "/Counter.json",
    JSON.stringify(CounterArtifact, null, 2)
  );
}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

//然后执行脚本 npx hardhat run scripts/deploy_counter.js --network development
      // scripts/deploy_counter.js
const hre = require("hardhat");
async function main() {
  //await hre.run('compile');
  const Counter = await hre.ethers.getContractFactory("Counter");
  const counter = await Counter.deploy(0);

  await counter.deployed();
  console.log("Counter deployed to:", counter.address);
  saveFrontendFiles(counter);
}

function saveFrontendFiles(counter) {
  const fs = require("fs");
  const contractsDir = "./data";

  if (!fs.existsSync(contractsDir)) {
    fs.mkdirSync(contractsDir);
  }

  fs.writeFileSync(
    contractsDir + "/contract-address.json",
    JSON.stringify({
      Counter: counter.address
    }, undefined, 2)
  );

  const CounterArtifact = artifacts.readArtifactSync("Counter");

  fs.writeFileSync(
    contractsDir + "/Counter.json",
    JSON.stringify(CounterArtifact, null, 2)
  );
}
main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

//然后执行脚本 npx hardhat run scripts/deploy_counter.js --network development

    2. 新建action.js实现前端调用合约的逻辑

      js
      const {
  ethers
} = require("hardhat")
const CounterArtifact = require("../data/Counter.json")
const contractAddress = require("../data/contract-address.json");

(async () => {
  // init
  const provider = new ethers.providers.JsonRpcProvider('http://127.0.0.1:8545/');

  // Then, we initialize the contract using that provider and the token's
  // artifact. You can do this same thing with your contracts.
  const counter = new ethers.Contract(
    contractAddress.Counter,
    CounterArtifact.abi,
    provider.getSigner(0)
  );

  console.log("counter值是：",await counter.counter())

  await counter.count();
  console.log("counter值是：",await counter.counter())

})()
      const {
  ethers
} = require("hardhat")
const CounterArtifact = require("../data/Counter.json")
const contractAddress = require("../data/contract-address.json");

(async () => {
  // init
  const provider = new ethers.providers.JsonRpcProvider('http://127.0.0.1:8545/');

  // Then, we initialize the contract using that provider and the token's
  // artifact. You can do this same thing with your contracts.
  const counter = new ethers.Contract(
    contractAddress.Counter,
    CounterArtifact.abi,
    provider.getSigner(0)
  );

  console.log("counter值是：",await counter.counter())

  await counter.count();
  console.log("counter值是：",await counter.counter())

})()