• 发币合约


    pragma solidity ^0.4.24;

    //标准ERC20Token接口
    contract ERC20Token{
    uint256 public totalSupply;
    function balanceOf(address _owner) public constant returns (uint256 balance);
    function transfer(address _to, uint256 _value) public returns (bool success);
    function transferFrom(address _from, address _to, uint256 _value) public returns(bool success);
    function approve(address _spender, uint256 _value) public returns (bool success);
    function allowance(address _owner, address _spender) public constant returns(uint256 remaining);

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);
    

    }
    //东大门EastToken
    contract EastToken is ERC20Token {
    string public name; //名称
    string public symbol; //token简称
    uint8 public decimals; //返回token使用的小数点后几位

    mapping (address => uint256) public balances;
    mapping (address => mapping (address => uint256)) public allowed;
    //构造函数
    constructor(uint256 _initialAmount, string _tokenName, uint8 _decimals, string _tokenSymbol) public {
        totalSupply = _initialAmount * 10 ** uint256(_decimals);        // 设置初始总量
        balances[msg.sender] = totalSupply;                              //初始token数量给予消息发送者,即合约的创建者
        name = _tokenName;
        decimals = _decimals;
        symbol = _tokenSymbol;
    }
    //调用者转账给to地址
    function transfer(address _to, uint256 _value) public returns (bool success) {
        //默认totalSupply不会超过最大值 (2^256 - 1),避免溢出的异常
        require(balances[msg.sender] >= _value && balances[_to] + _value > balances[_to]);
        require(_to != 0x0);                             //不能转空地址
        balances[msg.sender] -= _value;                  //从消息发送者账户中减去token数量_value
        balances[_to] += _value;                         //往接收账户增加token数量_value
        emit Transfer(msg.sender, _to, _value);          //触发转币交易事件
        return true;
    }
    //第三方调用转账
    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(balances[_from] >= _value && allowed[_from][msg.sender] >= _value);
        balances[_to] += _value;                          //接收账户增加token数量_value
        balances[_from] -= _value;                        //支出账户_from减去token数量_value
        allowed[_from][msg.sender] -= _value;             //消息发送者可以从账户_from中转出的数量减少_value
        emit Transfer(_from, _to, _value);                //触发转币交易事件
        return true;
    }
    //查询_owner的余额
    function balanceOf(address _owner) public constant returns (uint256 balance) {
        return balances[_owner];
    }
    //授权_spender在spender中花费_value
    function approve(address _spender, uint256 _value) public returns (bool success){
        allowed[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }
    //允许_spender从_owner中转出的token数
    function allowance(address _owner, address _spender) public constant returns (uint256 remaining) {
        return allowed[_owner][_spender];
    }
    

    //批转10000
    }

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  • 原文地址:https://www.cnblogs.com/xiaocongcong888/p/9708214.html
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