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前言

目前市場(chǎng)上很多token都是基于以太坊的ERC-20代幣，ERC20是以太坊定義的一個(gè)代幣標(biāo)準(zhǔn)。通過以太坊智能合約是可以比較輕松的發(fā)行自己的代幣的，今天就和大家一起學(xué)習(xí)一下，如何一步步創(chuàng)建自己的代幣。

環(huán)境準(zhǔn)備

1、Chrome瀏覽器
2、Chrome瀏覽器安裝MetaMask插件

metamask部署

進(jìn)入metamask頁面，選擇Ropsten Test Network網(wǎng)絡(luò)（為了省手續(xù)費(fèi)，這里選擇測(cè)試網(wǎng)絡(luò)）?？纯醋约旱馁~號(hào)中，是否有一定的eth，如果沒有，給測(cè)試賬號(hào)申請(qǐng)一點(diǎn)eth。

這時(shí)候，可以看到，測(cè)試賬戶里面有eth了（我當(dāng)時(shí)多點(diǎn)了幾次，用不了這么多，申請(qǐng)幾個(gè)就行了）

編寫代幣合約代碼

這部分大家可以參考ERC20 官方標(biāo)準(zhǔn)示范代碼

pragma solidity ^0.4.16;

interface tokenRecipient { function receiveApproval(address _from, uint256 _value, address _token, bytes _extraData) public; }

contract TokenERC20 {
    string public name;
    string public symbol;
    uint8 public decimals = 18;  // 18 是建議的默認(rèn)值
    uint256 public totalSupply;

    mapping (address => uint256) public balanceOf;  // 
    mapping (address => mapping (address => uint256)) public allowance;

    event Transfer(address indexed from, address indexed to, uint256 value);

    event Burn(address indexed from, uint256 value);


    function TokenERC20(uint256 initialSupply, string tokenName, string tokenSymbol) public {
        totalSupply = initialSupply * 10 ** uint256(decimals);
        balanceOf[msg.sender] = totalSupply;
        name = tokenName;
        symbol = tokenSymbol;
    }


    function _transfer(address _from, address _to, uint _value) internal {
        require(_to != 0x0);
        require(balanceOf[_from] >= _value);
        require(balanceOf[_to] + _value > balanceOf[_to]);
        uint previousBalances = balanceOf[_from] + balanceOf[_to];
        balanceOf[_from] -= _value;
        balanceOf[_to] += _value;
        Transfer(_from, _to, _value);
        assert(balanceOf[_from] + balanceOf[_to] == previousBalances);
    }

    function transfer(address _to, uint256 _value) public {
        _transfer(msg.sender, _to, _value);
    }

    function transferFrom(address _from, address _to, uint256 _value) public returns (bool success) {
        require(_value <= allowance[_from][msg.sender]);     // Check allowance
        allowance[_from][msg.sender] -= _value;
        _transfer(_from, _to, _value);
        return true;
    }

    function approve(address _spender, uint256 _value) public
        returns (bool success) {
        allowance[msg.sender][_spender] = _value;
        return true;
    }

    function approveAndCall(address _spender, uint256 _value, bytes _extraData) public returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(msg.sender, _value, this, _extraData);
            return true;
        }
    }

    function burn(uint256 _value) public returns (bool success) {
        require(balanceOf[msg.sender] >= _value);
        balanceOf[msg.sender] -= _value;
        totalSupply -= _value;
        Burn(msg.sender, _value);
        return true;
    }

    function burnFrom(address _from, uint256 _value) public returns (bool success) {
        require(balanceOf[_from] >= _value);
        require(_value <= allowance[_from][msg.sender]);
        balanceOf[_from] -= _value;
        allowance[_from][msg.sender] -= _value;
        totalSupply -= _value;
        Burn(_from, _value);
        return true;
    }
}

把上面這段合約代碼拷貝到Remix Solidity IDE,這是一個(gè)solidity在線編輯器，同時(shí)會(huì)同步metamask的賬戶信息。

編譯無誤的話，可以按照如下配置去設(shè)置