remix 学习零散2

提问 override 这个在solity里面是什么修饰符

https://www.alchemy.com/faucets/ethereum-sepolia

2024年改版之后 Sepolia 测试网水龙头

3天可以领0.1个测试币

eth 水龙头

提问

contract hyChainToken is ERC20 {
    constructor() ERC20("hyChainToken", "HYC") {
        _mint(msg.sender, 1000 * 10 ** decimals());
    }
}

 _mint(msg.sender, 1000 * 10 ** decimals());

这个表示要铸造多少个

提问 这个 IERC20 这个有什么用,

// SPDX-License-Identifier: GPL-3.0

pragma solidity >=0.8.2 <0.9.0;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";

contract ReceiveTokenContract {
    IERC20 myToken;

    constructor(address _tokenAddress) {
        myToken = IERC20(_tokenAddress);
    }

    function transferFrom(uint _amount) public {
        myToken.transferFrom(msg.sender, address(this), _amount);
    }

    function getBanlance(address _address) public view returns (uint) {
        return myToken.balanceOf(_address);
    }
}