49-Solidity8.0-小猪存钱罐

源码：

pragma solidity ^0.8.7;

contract PiggyBank {
    event Deposit(uint amount);
    event Withdraw(uint amount);

    address public owner = msg.sender;

    receive() external payable {
        emit Deposit(msg.value);
    }

    function withdraw() external {
        require (msg.sender == owner, "not owner");
        emit Withdraw(address(this).balance);
        selfdestruct(payable(msg.sender));
    }
}