在SIPC上发行代币 · SimpleChain开发文档

如何在SimpleChain上发行数字资产

前提条件

实现链上发币的准备工作，包括:

SimpleChain 的下载以及部署。
启动节点。
创建账户。
确保账户解锁并有 token。

准备工作

1.了解 ERC20 代币标准。

说明:在 SimpleChain 上实现代币需要遵循 ERC20 标准。

//ERC20Token.sol
//ERC 合约标准，该标准规定在发 Token 之前，需要指定 token 的名称、标识、总量、实现合 
//约标准函数等    
pragma solidity ^0.4.26; 

contract ERC20Token {
    //获取 token 名称
    function name() public constant returns (string name);
    //获取 token 标识
    function symbol() public constant returns (string symbol);
    //获取 token 的最小分割量
    function decimals() public constant returns (uint8 decimals);
    //获取 token 的总量
    function totalSupply() public constant returns (uint256 totalSupply);
    //获取_owner 账户当前的 token 量
    function balanceOf(address _owner) public constant returns (uint256 balance);
    //转账交易
    function transfer(address _to, uint256 _value) public returns (bool success);
    //由_from 向_to 进行转账
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success);
    //许可_spender 能从调用合约方法的账户转出总量为_value 的 token
    function approve(address _spender, uint256 _value) public returns (bool success);
    //获取_spender 可以从账户_owner 中转出 token 的剩余数量
    function allowance(address _owner, address _spender) public constant returns (uint remaining);
    //转账事件(transfer、transferFrom 会触发该事件)
    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    //许可事件(approve 会触发该事件)
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
}

2.编写符合ERC20标准的代币合约。

//Mytoken.sol
pragma solidity ^0.4.26;
import "./ERC20Token.sol";
  
contract MyToken is ERC20Token {
    string private _name;
    string private _symbol;
    uint8 private _decimals = 18; //此处建议为 18，代表最小单位为 0.1^18 
    uint256 private _totalSupply;

    //存储账户的 token 总量
    mapping(address => uint256) private _balances;
    //存储前一个address允许后一个address转出token的剩余数量 
    mapping(address => mapping(address => uint256)) private _allowances;

    function MyToken(uint256 initialSupply, string tokenName, string tokenSymbol) public{
        _name = tokenName;
        _symbol = tokenSymbol;
        _totalSupply = initialSupply * 10 ** uint256(_decimals);
        _balances[msg.sender] = _totalSupply;
   }

   function name() public constant returns (string name){ 
        name = _name;
   }
   function symbol() public constant returns (string symbol){ 
        symbol = _symbol;
   }
   function decimals() public constant returns (uint8 decimals){ 
        decimals = _decimals;
   }
   function totalSupply() public constant returns (uint256 totalSupply){ 
        totalSupply = _totalSupply;                
   }
   function balanceOf(address _owner) public constant returns (uint256 balance){ 
        balance = _balances[_owner];
   }
   function transfer(address _to, uint256 _value) public returns (bool success){ 
       require(_balances[msg.sender] >= _value); //保证发出交易的账户 token 足够完成转账
       _balances[msg.sender] -= _value; _balances[_to] += value; Transfer(msg.sender, _to, _value); success = true;
   }
   function transferFrom(address _from, address _to, uint256 _value) public returns (bool success){
       require(_balances[_from] >= _value); //保证_from 账户 token 足够完成转 账
       require(_allowances[_from][msg.sender] >= _value); //保证_from 账户允许 执行账户转出的 token 剩余量足够
       _balances[_from] -= _value; _allowances[_from][msg.sender] -= _value; _balances[_to] += _value;
       Transfer(_from, _to, _value);
       success = true;
   }
                             }
   //许可_spender 能从调用合约方法的账户转出总量为_value 的 token
   function approve(address _spender, uint256 _value) public returns (bool success){
       _allowances[msg.sender][_spender] = _value; 
       Approval(msg.sender, _spender, _value); success = true;
   }
              
   //获取_spender 可以从账户_owner 中转出 token 的剩余数量
   function allowance(address _owner, address _spender) public constant returns (uint256 remaining){
        remaining = _allowances[_owner][_spender]; 
    }
}

合约编译