区块链程序模拟实现
区块链技术是一种去中心化的分布式数据库技术,它以区块为基本单位,通过链式结构将各个区块连接在一起,实现数据的安全传输和存储。在实现区块链程序模拟时,我们可以采用简化的方式,以理解其基本原理和实现方法为主。下面我将介绍一个简单的区块链程序模拟实现,以帮助您更好地理解区块链技术。
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区块链程序模拟实现
在这个简单的区块链模拟实现中,我们将模拟一个简化的区块链网络,包括区块的创建、交易的添加和验证等基本功能。
// 定义区块类
class Block {
constructor(index, timestamp, data, previousHash = '') {
this.index = index;
this.timestamp = timestamp;
this.data = data;
this.previousHash = previousHash;
this.hash = this.calculateHash();
}
calculateHash() {
return SHA256(this.index this.previousHash this.timestamp JSON.stringify(this.data)).toString();
}
}
// 定义区块链类
class Blockchain {
constructor() {
this.chain = [this.createGenesisBlock()];
}
createGenesisBlock() {
return new Block(0, "01/01/2020", "Genesis block", "0");
}
getLatestBlock() {
return this.chain[this.chain.length 1];
}
addBlock(newBlock) {
newBlock.previousHash = this.getLatestBlock().hash;
newBlock.hash = newBlock.calculateHash();
this.chain.push(newBlock);
}
isChainValid() {
for (let i = 1; i < this.chain.length; i ) {
const currentBlock = this.chain[i];
const previousBlock = this.chain[i 1];
if (currentBlock.hash !== currentBlock.calculateHash()) {
return false;
}
if (currentBlock.previousHash !== previousBlock.hash) {
return false;
}
}
return true;
}
}
// 创建一个简单的区块链实例并添加一些示例数据
let myBlockchain = new Blockchain();
myBlockchain.addBlock(new Block(1, "02/01/2020", { amount: 4 }));
myBlockchain.addBlock(new Block(2, "03/01/2020", { amount: 8 }));
// 输出区块链的内容和验证区块链的有效性
console.log(JSON.stringify(myBlockchain, null, 4));
console.log('Is blockchain valid? ' myBlockchain.isChainValid());