📅 最后修改于: 2023-12-03 15:22:22.770000 🧑 作者: Mango
随着区块链技术逐渐成熟，其在各领域的应用也越来越广泛。其中之一就是在投票领域中，使用区块链来构建去中心化投票系统。
传统的投票系统存在着诸多问题，如投票造假、数据篡改、投票安全性不高等等。而借助区块链技术，可以有效地解决这些问题。
区块链的去中心化特点，使其成为构建投票系统的理想选择。具体实现原理如下：
下面以以太坊为例，介绍一下如何使用以太坊构建一个简单的去中心化投票系统。
contract Voting {
struct Voter {
bool isRegistered; //是否注册
bool hasVoted; //是否已经投票
uint votedFor; //投票选项编号
uint weight; //该投票人的权重
}
struct Option {
uint voteCount; //该选项获得的投票数
}
mapping(address => Voter) public voters;
Option[] public options;
address public chairperson;
constructor(uint8 _numOfOptions) public {
chairperson = msg.sender;
voters[chairperson].weight = 1;
options.length = _numOfOptions;
}
function register(address _voter) public {
require(msg.sender == chairperson);
require(!voters[_voter].isRegistered);
voters[_voter].isRegistered = true;
voters[_voter].weight = 1;
}
function vote(uint _option) public {
Voter storage sender = voters[msg.sender];
require(sender.isRegistered && !sender.hasVoted);
sender.hasVoted = true;
sender.votedFor = _option;
options[_option].voteCount += sender.weight;
}
}
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Voting DAPP</title>
<script src="./web3.min.js"></script>
<script src="./voting.js"></script>
</head>
<body>
<h1>投票系统</h1>
<div id="voters">
<h2>投票人列表</h2>
<ul id="voterList"></ul>
</div>
<div id="options">
<h2>投票选项列表</h2>
<ul id="optionList"></ul>
</div>
<div id="results">
<h2>投票结果</h2>
<ul id="resultList"></ul>
</div>
</body>
</html>
window.addEventListener('load', function() {
if (typeof web3 !== 'undefined') {
console.log('web3已经初始化');
web3Provider = web3.currentProvider;
} else {
console.log('没有检测到web3');
web3Provider = new Web3.providers.HttpProvider('http://localhost:8545');
}
web3 = new Web3(web3Provider);
var contractInstance;
var contractAddress = '0x1b65d7b130873c8cc9777ca2f0d90301c951b794';
var abi = [
{
"constant":true,
"inputs":[],
"name":"chairperson",
"outputs":[
{
"name":"",
"type":"address"
}
],
"payable":false,
"stateMutability":"view",
"type":"function"
},
{
"constant":false,
"inputs":[
{
"name":"_voter",
"type":"address"
}
],
"name":"register",
"outputs":[],
"payable":false,
"stateMutability":"nonpayable",
"type":"function"
},
{
"constant":false,
"inputs":[
{
"name":"_option",
"type":"uint256"
}
],
"name":"vote",
"outputs":[],
"payable":false,
"stateMutability":"nonpayable",
"type":"function"
},
{
"constant":true,
"inputs":[
{
"name":"",
"type":"address"
}
],
"name":"voters",
"outputs":[
{
"name":"isRegistered",
"type":"bool"
},
{
"name":"hasVoted",
"type":"bool"
},
{
"name":"votedFor",
"type":"uint256"
},
{
"name":"weight",
"type":"uint256"
}
],
"payable":false,
"stateMutability":"view",
"type":"function"
},
{
"constant":true,
"inputs":[
{
"name":"",
"type":"uint256"
}
],
"name":"options",
"outputs":[
{
"name":"voteCount",
"type":"uint256"
}
],
"payable":false,
"stateMutability":"view",
"type":"function"
},
{
"inputs":[
{
"name":"_numOfOptions",
"type":"uint8"
}
],
"payable":false,
"stateMutability":"nonpayable",
"type":"constructor"
}
];
contractInstance = web3.eth.contract(abi).at(contractAddress);
refreshVoterList();
refreshOptionList();
refreshResultList();
$("#registerVoter").click(function() {
var address = $("#voterAddress").val();
contractInstance.register(address, {from: web3.eth.accounts[0]}, function(error, result) {
if (!error) {
$("#voterAddress").val("");
refreshVoterList();
} else {
console.log(error);
}
});
});
$("#vote").click(function() {
var option = $("#option").val();
contractInstance.vote(option, {from: web3.eth.accounts[0]}, function(error, result) {
if (!error) {
$("#option").val("");
refreshResultList();
} else {
console.log(error);
}
});
});
function refreshVoterList() {
$("#voterList").empty();
for (var voter in contractInstance.voters) {
if (contractInstance.voters[voter].isRegistered) {
var element = '<li>' + voter + '</li>';
$("#voterList").append(element);
}
}
}
function refreshOptionList() {
$("#optionList").empty();
for (var i = 0; i < contractInstance.options.length; i++) {
var element = '<li>' + i + '</li>';
$("#optionList").append(element);
}
}
function refreshResultList() {
$("#resultList").empty();
for (var i = 0; i < contractInstance.options.length; i++) {
var element = '<li>' + i + ' - ' + contractInstance.options[i].voteCount + '</li>';
$("#resultList").append(element);
}
}
});
本文介绍了如何使用区块链技术构建一个去中心化投票系统，以以太坊为例，通过智能合约和前端代码，实现了投票人注册、投票选项选择、投票以及投票结果显示等功能。去中心化的特点，保证了投票的公正性和安全性，有效地解决了传统投票系统的一些问题。