Hardhat 環境設定

Introduction Hardhat

Hardhat 是 Ethereum 智能合約開發的完整環境工具，用於編譯、測試、部署和除錯 Solidity 程式碼。

Build node envorinment

use terminal in Mac

curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.40.3/install.sh | bash\. "$HOME/.nvm/nvm.sh”
nvm install 22
nvm use 22
nvm alias default 22
npm install npm --global
npm init

Install hardhat package

npm install --save-dev hardhat@^2.22.6

Initial a hardhat project

npx hardhat init
npm install --save-dev @nomicfoundation/hardhat-toolbox

Write a contract

We use hardhat tutorial contract example

4. Writing and compiling smart contracts | Ethereum development environment for professionals by Nomic Foundation

Create a “contracts” dictionary

mkdir contracts

Create a .sol file

touch xxx.sol

Paste the contract example from hardhat tutorial

//SPDX-License-Identifier: UNLICENSED

// Solidity files have to start with this pragma.
// It will be used by the Solidity compiler to validate its version.
pragma solidity ^0.8.0;

// This is the main building block for smart contracts.
contract Token {
    // Some string type variables to identify the token.
    string public name = "My Hardhat Token";
    string public symbol = "MHT";

    // The fixed amount of tokens, stored in an unsigned integer type variable.
    uint256 public totalSupply = 1000000;

    // An address type variable is used to store ethereum accounts.
    address public owner;

    // A mapping is a key/value map. Here we store each account's balance.
    mapping(address => uint256) balances;

    // The Transfer event helps off-chain applications understand
    // what happens within your contract.
    event Transfer(address indexed _from, address indexed _to, uint256 _value);

    /**
     * Contract initialization.
     */
    constructor() {
        // The totalSupply is assigned to the transaction sender, which is the
        // account that is deploying the contract.
        balances[msg.sender] = totalSupply;
        owner = msg.sender;
    }

    /**
     * A function to transfer tokens.
     *
     * The `external` modifier makes a function *only* callable from *outside*
     * the contract.
     */
    function transfer(address to, uint256 amount) external {
        // Check if the transaction sender has enough tokens.
        // If `require`'s first argument evaluates to `false`, the
        // transaction will revert.
        require(balances[msg.sender] >= amount, "Not enough tokens");

        // Transfer the amount.
        balances[msg.sender] -= amount;
        balances[to] += amount;

        // Notify off-chain applications of the transfer.
        emit Transfer(msg.sender, to, amount);
    }

    /**
     * Read only function to retrieve the token balance of a given account.
     *
     * The `view` modifier indicates that it doesn't modify the contract's
     * state, which allows us to call it without executing a transaction.
     */
    function balanceOf(address account) external view returns (uint256) {
        return balances[account];
    }
}

Compile

Use the compile command

npx hardhat compile

if success show

Compiled 14 Solidity files successfully (evm target: paris).