將以太坊封裝為 ERC20

將以太坊封裝為 ERC20 TOKEN

很多 DAPP 都是在處理 ERC20接口的 token, 其實很容易將以太坊封裝為 ERC20,這樣就可以統一處理,
至少我目前在做的雷電網絡就是這么處理的.

主要內容復制在網絡
https://programtheblockchain.com/posts/2018/05/26/wrapping-ether-in-an-erc20-token/

直接上代碼,核心部分是

pragma solidity ^0.4.24;import "baseerc20token.sol";contract EtherToken is BaseERC20Token {constructor(string _name, string _symbol)BaseERC20Token(0, 18, _name, _symbol) public{}function buy() public payable {balanceOf[msg.sender] += msg.value;totalSupply += msg.value;emit Transfer(address(0), msg.sender, msg.value);}function sell(uint256 amount) public {require(balanceOf[msg.sender] >= amount, "Insufficient balance.");balanceOf[msg.sender] -= amount;totalSupply -= amount;msg.sender.transfer(amount);emit Transfer(msg.sender, address(0), amount);}
}

它提供了以太坊和 ERC20互換的接口,換成 ERC20以后就很簡單了.
實際上baseerc20token.sol只是一個非常標準的 ERC20實現

pragma solidity ^0.4.23;contract BaseERC20Token {mapping (address => uint256) public balanceOf;string public name;string public symbol;uint8 public decimals;uint256 public totalSupply;event Transfer(address indexed from, address indexed to, uint256 value);constructor (uint256 _totalSupply,uint8 _decimals,string _name,string _symbol)public{name = _name;symbol = _symbol;decimals = _decimals;totalSupply = _totalSupply;balanceOf[msg.sender] = _totalSupply;emit Transfer(address(0), msg.sender, _totalSupply);}function transfer(address to, uint256 value) public returns (bool success) {require(balanceOf[msg.sender] >= value);balanceOf[msg.sender] -= value;balanceOf[to] += value;emit Transfer(msg.sender, to, value);return true;}event Approval(address indexed owner, address indexed spender, uint256 value);mapping(address => mapping(address => uint256)) public allowance;function approve(address spender, uint256 value)publicreturns (bool success){allowance[msg.sender][spender] = value;emit Approval(msg.sender, spender, value);return true;}function transferFrom(address from, address to, uint256 value)publicreturns (bool success){require(value <= balanceOf[from]);require(value <= allowance[from][msg.sender]);balanceOf[from] -= value;balanceOf[to] += value;allowance[from][msg.sender] -= value;emit Transfer(from, to, value);return true;}
}

這樣簡單部署,就可以在雷電網絡中將以太坊當做普通的 ERC20 TOKEN進行處理了.