使用truffle框架编写简单的加密货币

1 创建项目

通过truffle init

$ mkdir EncryptedToken
$ cd EncryptedToken/
$ truffle init
Downloading...
Unpacking...
Setting up...
Unbox successful. Sweet!

Commands:

  Compile:        truffle compile
  Migrate:        truffle migrate
  Test contracts: truffle test

2 编写代码

2.1 在contracts目录下新建EncryptedToken.sol文件代码如下：

pragma solidity ^0.4.4;

contract EncryptedToken {
    uint256 INITIAL_SUPPLY = 888888; //提供币的总量

    mapping (address => uint256) balances;
    constructor() public {
        balances[msg.sender] = INITIAL_SUPPLY;
    }
    // 转账到一个指定的地点
    function transfer(address _to,uint256 _amount) public {
        assert(balances[msg.sender] > _amount);
        balances[msg.sender] -= _amount;
        balances[_to] += _amount;
    }
    //查看指定地址的余额
    function balanceOf(address _owner)  public view returns (uint256) {
        return balances[_owner];
    }
}

/**
命令：
进入控制台：$ truffle develop
编译：compile
部署： migrate  
第二次部署：migrate --reset
创建实例：let contract = EncryptedToken.deployed().then(instance => contract = instance);

Accounts:
(0) 0x627306090abab3a6e1400e9345bc60c78a8bef57
(1) 0xf17f52151ebef6c7334fad080c5704d77216b732

查看余额：
contract.balanceOf("0x627306090abab3a6e1400e9345bc60c78a8bef57")
contract.balanceOf("0xf17f52151ebef6c7334fad080c5704d77216b732")

转账：
contract.transfer("0xf17f52151ebef6c7334fad080c5704d77216b732",888)
 */

2.1 在migrations目录下新建2_deloy_encryptedtoken.js文件，代码如下：

var EncryptedToken = artifacts.require("./EncryptedToken.sol");

module.exports = function(deployer) {
  deployer.deploy(EncryptedToken);
};

3 代码的编译和部署

进入控制台：

$ truffle develop
Truffle Develop started at http://127.0.0.1:9545/

Accounts:
(0) 0x627306090abab3a6e1400e9345bc60c78a8bef57
(1) 0xf17f52151ebef6c7334fad080c5704d77216b732
(2) 0xc5fdf4076b8f3a5357c5e395ab970b5b54098fef
(3) 0x821aea9a577a9b44299b9c15c88cf3087f3b5544
(4) 0x0d1d4e623d10f9fba5db95830f7d3839406c6af2
(5) 0x2932b7a2355d6fecc4b5c0b6bd44cc31df247a2e
(6) 0x2191ef87e392377ec08e7c08eb105ef5448eced5
(7) 0x0f4f2ac550a1b4e2280d04c21cea7ebd822934b5
(8) 0x6330a553fc93768f612722bb8c2ec78ac90b3bbc
(9) 0x5aeda56215b167893e80b4fe645ba6d5bab767de

Private Keys:
(0) c87509a1c067bbde78beb793e6fa76530b6382a4c0241e5e4a9ec0a0f44dc0d3
(1) ae6ae8e5ccbfb04590405997ee2d52d2b330726137b875053c36d94e974d162f
(2) 0dbbe8e4ae425a6d2687f1a7e3ba17bc98c673636790f1b8ad91193c05875ef1
(3) c88b703fb08cbea894b6aeff5a544fb92e78a18e19814cd85da83b71f772aa6c
(4) 388c684f0ba1ef5017716adb5d21a053ea8e90277d0868337519f97bede61418
(5) 659cbb0e2411a44db63778987b1e22153c086a95eb6b18bdf89de078917abc63
(6) 82d052c865f5763aad42add438569276c00d3d88a2d062d36b2bae914d58b8c8
(7) aa3680d5d48a8283413f7a108367c7299ca73f553735860a87b08f39395618b7
(8) 0f62d96d6675f32685bbdb8ac13cda7c23436f63efbb9d07700d8669ff12b7c4
(9) 8d5366123cb560bb606379f90a0bfd4769eecc0557f1b362dcae9012b548b1e5

Mnemonic: candy maple cake sugar pudding cream honey rich smooth crumble sweet treat

⚠️  Important ⚠️  : This mnemonic was created for you by Truffle. It is not secure.
Ensure you do not use it on production blockchains, or else you risk losing funds.

编译：

truffle(develop)> compile
Compiling ./contracts/EncryptedToken.sol...
Compiling ./contracts/Migrations.sol...
Writing artifacts to ./build/contracts

部署：

truffle(develop)> migrate
Using network 'develop'.

Running migration: 1_initial_migration.js
  Deploying Migrations...
  ... 0x249aed24bd6a95537a5acb3b5a9ea8c920869b0605ef560c0eb9dfc376bf9a61
  Migrations: 0x8cdaf0cd259887258bc13a92c0a6da92698644c0
Saving successful migration to network...
  ... 0xd7bc86d31bee32fa3988f1c1eabce403a1b5d570340a3a9cdba53a472ee8c956
Saving artifacts...
Running migration: 2_deloy_encryptedtoken.js
  Deploying EncryptedToken...
  ... 0x403076503ae9a265651cdbaaf4fc97f26af810a484b0ba35ffed8a2ff3288f3b
  EncryptedToken: 0x345ca3e014aaf5dca488057592ee47305d9b3e10
Saving successful migration to network...
  ... 0xf36163615f41ef7ed8f4a8f192149a0bf633fe1a2398ce001bf44c43dc7bdda0
Saving artifacts...

4 运行合约

创建实例：

truffle(develop)> let contract = EncryptedToken.deployed().then(instance => contract = instance);
undefined

查看地址0x627306090abab3a6e1400e9345bc60c78a8bef57和0xf17f52151ebef6c7334fad080c5704d77216b732中的余额：

truffle(develop)> contract.balanceOf("0x627306090abab3a6e1400e9345bc60c78a8bef57")
BigNumber { s: 1, e: 5, c: [ 888888 ] }
truffle(develop)> contract.balanceOf("0xf17f52151ebef6c7334fad080c5704d77216b732")
BigNumber { s: 1, e: 0, c: [ 0 ] }

转账给888个币给0xf17f52151ebef6c7334fad080c5704d77216b732：

truffle(develop)> contract.transfer("0xf17f52151ebef6c7334fad080c5704d77216b732",888)
{ tx:
   '0x88dd855050af4033c005b758bea3de2d8ce0ef95bf067dad242537f328deb581',
  receipt:
   { transactionHash:
      '0x88dd855050af4033c005b758bea3de2d8ce0ef95bf067dad242537f328deb581',
     transactionIndex: 0,
     blockHash:
      '0x7ec60afc574e62c5d4d024723a31795259261ce20b74837a43e79f6581e1ce9d',
     blockNumber: 5,
     gasUsed: 49147,
     cumulativeGasUsed: 49147,
     contractAddress: null,
     logs: [],
     status: '0x01',
     logsBloom:
      '0x00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000' },
  logs: [] }

再查看两个地址的余额情况：

truffle(develop)> contract.balanceOf("0x627306090abab3a6e1400e9345bc60c78a8bef57")
BigNumber { s: 1, e: 5, c: [ 888000 ] }
truffle(develop)> contract.balanceOf("0xf17f52151ebef6c7334fad080c5704d77216b732")
BigNumber { s: 1, e: 2, c: [ 888 ] }

5 命令总结

创建项目：$ truffle init
进入truffle控制台：$ truffle develop
编译：compile
部署： migrate
第二次部署：migrate --reset
创建实例：let contract = EncryptedToken.deployed().then(instance => contract = instance);