Solidity 学习记录_2_数据类型

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//存钱罐合约
pragma solidity ^0.8.0;

contract PiggyBank {
    address public owner;

    constructor() {
        owner = msg.sender;
    }

    // 接收 ETH
    receive() external payable {}

    // 查询余额
    function getBalance() public view returns (uint256) {
        return address(this).balance;
    }

    // 提取 ETH（只有 owner 可以）
    function withdraw() public {
        require(msg.sender == owner, "Only owner can withdraw");
        (bool success, ) = payable(owner).call{value: address(this).balance}("");
        require(success, "Withdraw failed");
    }
}

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pragma solidity ^0.8.0;

// 1. 定义 Counter 合约
contract Counter {
    // 计数状态变量
    uint public count;

    // 增加计数的函数
    function increment() public {
        count += 1;
    }

    // 获取当前计数的函数
    function getCount() public view returns (uint) {
        return count;
    }
}

// 2. 定义 CounterFactory 工厂合约
contract CounterFactory {
    // 存储创建的 Counter 合约实例
    Counter public counter;

    // 创建新的 Counter 合约
    function createCounter() public returns (address) {
        counter = new Counter();
        return address(counter);
    }

    // 调用 Counter 合约的 increment 函数
    function incrementCounter() public {
        // 检查合约是否已创建
        require(address(counter) != address(0), "Counter not created yet");
        counter.increment();
    }

    // 获取 Counter 合约的当前计数值
    function getCounterValue() public view returns (uint) {
        require(address(counter) != address(0), "Counter not created yet");
        return counter.getCount();
    }
}