Eth 部署智能合约

首先要开发以太坊的智能合约，需要EVM（以太坊虚拟机），也就是需要运行的环境，我们可以通过 geth 来设置开发环境：

geth --datadir testNet --dev console 2>> test.log

命令参数说明（更多命令详解可阅读Geth命令用法-参数详解篇）:
–dev 启用开发者网络（模式），开发者网络会使用POA共识，默认预分配一个开发者账户并且会自动开启挖矿。
–datadir 后面的参数是区块数据及秘钥存放目录。
第一次输入命令后，它会放在当前目录下新建一个testNet目录来存放数据。
console 进入控制台
2>> test.log 表示把控制台日志输出到test.log文件

然后就进入了以太坊客户端 console 界面。

在 console 里，你可以通过相关命令来建立账户、挖矿、转账、查看区块高度等。

接着，建立智能合约：

pragma solidity >=0.4.22 <0.6.0;
contract man {
    string word;
    
    constructor(string memory s) public {
        word = s;
    }
    
    function say() public view returns (string memory) {
        return word;
    }
}

可以在 remix （在线 solidity 编译器）编译你的代码

选择编译器版本，然后编译，再点击 detail ，弹出详细信息，

var s = "hello";
var manContract = web3.eth.contract([{"constant":true,"inputs":[],"name":"say","outputs":[{"name":"","type":"string"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"s","type":"string"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"}]);
var man = manContract.new(
   s,
   {
     from: web3.eth.accounts[2], 
     data: '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', 
     gas: '4700000'
   }, function (e, contract){
    console.log(e, contract);
    if (typeof contract.address !== 'undefined') {
         console.log('Contract mined! address: ' + contract.address + ' transactionHash: ' + contract.transactionHash);
    }
 })

将文本复制起来，修改其中的变量，from 地址等，然后在 geth console 中输入，则部署成功

运行合约，发现error

解决方式：

eth.defaultAccount=eth.coinbase

最后得到正确结果：