上一篇文章实现了搭建私有链，以下进行智能合约的部署
一、 编写合约
简单的乘法例子：
pragma solidity ^0.4.2;
contract test {
function multiply(uint a) returns(uint d) { return a * 7; } }
二、 编译合约
推荐网站：here
得到：Interface 和 Bytecode 和 Web3 deploy
Bytecode: 6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a723058206f9974e7f2c8329cbc09530d06d001018bfeca369c7cd8f9d565298adbdd2a9c0029
Interface: [{"constant":false,"inputs":[{"name":"a","type":"uint256"}],"name":"multiply","outputs":[{"name":"d","type":"uint256"}],"payable":false,"stateMutability":"nonpayable","type":"function"}] Web3 deploy: var browser_ballot_sol_testContract = web3.eth.contract([{"constant":false,"inputs":[{"name":"a","type":"uint256"}],"name":"multiply","outputs":[{"name":"d","type":"uint256"}],"payable":false,"stateMutability":"nonpayable","type":"function"}]); var browser_ballot_sol_test = browser_ballot_sol_testContract.new( { from: web3.eth.accounts[0], data: '0x6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a723058206f9974e7f2c8329cbc09530d06d001018bfeca369c7cd8f9d565298adbdd2a9c0029', gas: '4300000' }, function (e, contract){ console.log(e, contract); if (typeof contract.address !== 'undefined') { console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash); } })
三、 部署合约
在部署合约前，我们要明确需要以下几项条件：
- 一个有Ether的账户；
- 该账户已解锁；
- 编译合约得到的abi和code。
所以首先需要做以下工作：
//创建账户
personal.newAccount('密码')
//挖矿，获得ether
miner.start()
miner.stop()
//账户解锁
personal.unlockAccount("第一个账户地址", "密码")
第一步： 获取abi信息，即上述编译得到的interface
abi = [{"constant":false,"inputs":[{"name":"a","type":"uint256"}],"name":"multiply","outputs":[{"name":"d","type":"uint256"}],"payable":false,"stateMutability":"nonpayable","type":"function"}]
得到结果：
[{
constant: false,
inputs: [{
name: "a",
type: "uint256" }], name: "multiply", outputs: [{ name: "d", type: "uint256" }], payable: false, stateMutability: "nonpayable", type: "function" }] >
第二步：
multiplyContract = web3.eth.contract(abi)得到结果：
{
abi: [{
constant: false,
inputs: [{...}],
name: "multiply",
outputs: [{...}],
payable: false,
stateMutability: "nonpayable",
type: "function" }], eth: { accounts: ["0xbe98c12f918275591c9a43ec3c7bc44cfca50d2f"], blockNumber: 7, coinbase: "0xbe98c12f918275591c9a43ec3c7bc44cfca50d2f", compile: { lll: function(), serpent: function(), solidity: function() }, defaultAccount: undefined, defaultBlock: "latest", gasPrice: 18000000000, hashrate: 0, mining: false, pendingTransactions: [], protocolVersion: "0x3f", syncing: false, call: function(), ... (一堆function) }
第三步： 复制 Web3 deploy 到命令行
multiply = multiplyContract.new(
{
from: web3.eth.accounts[0],
data: '0x6060604052341561000f57600080fd5b5b60ab8061001e6000396000f30060606040526000357c0100000000000000000000000000000000000000000000000000000000900463ffffffff168063c6888fa114603d575b600080fd5b3415604757600080fd5b605b60048080359060200190919050506071565b6040518082815260200191505060405180910390f35b60006007820290505b9190505600a165627a7a723058206f9974e7f2c8329cbc09530d06d001018bfeca369c7cd8f9d565298adbdd2a9c0029',
gas: '4300000' //改为300000 }, function (e, contract){ console.log(e, contract); if (typeof contract.address !== 'undefined') { console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash); } })
得到结果
{
abi: [{
constant: false,
inputs: [{...}],
name: "multiply",
outputs: [{...}],
payable: false,
stateMutability: "nonpayable",
type: "function" }], address: undefined, transactionHash: "0x87400471a0e32edcfa9e1ca621d08a318e9abb85299d280deb8bc199e118427f" }
==> 在这一步，可能你会得到一条错误信息：
invalid sender undefined
解决方法: 在genesis.json文件中，chainId 不能设置为0。 如果你完全按照github上给的官方配置文件，就会产生这个错误
==> 在这一步，可能你会得到一条错误信息：
Error: authentication needed: password or unlock undefined
解决方法：先解锁账户啦
personal.unlockAccount("第一个账户地址", "密码")
==> 在这一步，可能你还会遇到这个问题：
Error: exceeds block gas limit undefined
The contract code couldn't be stored, please check your gas amount. undefined
解决方法：把gas改为300000。直接从那个网站的Web3 deploy 复制可能是4300000，然后改成300000，就没问题了。
猜测原因：
eth.getBlock("pending").gasLimit
web3.eth.estimateGas({data: bytecode})
可以先输入这两条来预判一下范围，取中间值。
第四步：然后我们需要挖矿确认
miner.start()
等待一会，你会得到一条信息：
Contract mined! address: 0xdb385bc97ed9fbac62920102d5edc7c4bf993c79 transactionHash: 0x87400471a0e32edcfa9e1ca621d08a318e9abb85299d280deb8bc199e118427f
==> 就代表部署成功啦。
miner.stop()
四、合约交互
第一步：获取合约对象
MyContract = eth.contract(abi)
得到结果：
{
abi: [{
constant: false,
inputs: [{...}],
name: "multiply",
outputs: [{...}],
payable: false,
stateMutability: "nonpayable",
type: "function" }], eth: { accounts: ["0xd88ad6d115ed640b69f01e24ff1433f75d5c8f87"], blockNumber: 4, coinbase: "0xd88ad6d115ed640b69f01e24ff1433f75d5c8f87", compile: { lll: function(), serpent: function(), solidity: function() }, defaultAccount: undefined, defaultBlock: "latest", gasPrice: 18000000000, hashrate: 612, mining: false, pendingTransactions: [], ...（一堆function） }
第二步：实例化合约
myContract = MyContract.at(multiply.address)
得到结果：
{
abi: [{
constant: false,
inputs: [{...}],
name: "multiply",
outputs: [{...}],
payable: false,
stateMutability: "nonpayable",
type: "function" }], address: "0xdb385bc97ed9fbac62920102d5edc7c4bf993c79", transactionHash: null, allEvents: function(), multiply: function() }
第三步：调用合约
myContract.multiply.call(5)
得到结果：
35
五、在电脑B调用该合约
确定两台电脑已成功连接。电脑B上新建账户，并解锁。
1. abi = [{constant:false,inputs:[{name:'a',type:'uint256'}],name:'multiply',outputs:[{name:'d',type:'uint256'}],type:'function'}] //合约的abi 2. address = 0xdb385bc97ed9fbac62920102d5edc7c4bf993c79 // 合约地址 3. myContract = web3.eth.contract(abi).at(address) ==> 然后就可以调用使用了 myContract.multiply.call(5) 得到结果：35