简单的Go语言实现的区块链应用案例

package main

import (
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"time"
)

// Block 结构体
type Block struct {
	Index        int
	Timestamp    string
	Transactions []string
	PrevBlockHash string
	Hash          string
}

// Blockchain 结构体
type Blockchain struct {
	Blocks []Block
}

// NewBlockchain 创建一个新的区块链
func NewBlockchain() *Blockchain {
	return &Blockchain{}
}

// AddBlock 添加一个新的区块到区块链
func (bc *Blockchain) AddBlock(transactions []string) {
	prevBlock := bc.Blocks[len(bc.Blocks)-1]
	newBlock := Block{
		Index:        prevBlock.Index + 1,
		Timestamp:    time.Now().String(),
		Transactions: transactions,
		PrevBlockHash: prevBlock.Hash,
	}
	newBlock.Hash = newBlock.CalculateHash()
	bc.Blocks = append(bc.Blocks, newBlock)
}

// CalculateHash 计算区块的哈希值
func (b *Block) CalculateHash() string {
	record := fmt.Sprintf("%d%s%v%s", b.Index, b.Timestamp, b.Transactions, b.PrevBlockHash)
	h := sha256.New()
	h.Write([]byte(record))
	return hex.EncodeToString(h.Sum(nil))
}

// PrintBlockchain 打印区块链的内容
func (bc *Blockchain) PrintBlockchain() {
	for _, block := range bc.Blocks {
		fmt.Printf("Block %d\n", block.Index)
		fmt.Printf("Timestamp: %s\n", block.Timestamp)
		fmt.Printf("Transactions: %v\n", block.Transactions)
		fmt.Printf("PrevBlockHash: %s\n", block.PrevBlockHash)
		fmt.Printf("Hash: %s\n", block.Hash)
		fmt.Println("----------------------------")
	}
}

func main() {
	// 创建一个新的区块链
	blockchain := NewBlockchain()
	blockchain.Blocks = append(blockchain.Blocks, Block{
		Index:        0,
		Timestamp:    time.Now().String(),
		Transactions: []string{"Genesis Block"},
		PrevBlockHash: "",
		Hash:          "0",
	})

	// 添加一些区块
	blockchain.AddBlock([]string{"Alice -> Bob: 10 BTC"})
	blockchain.AddBlock([]string{"Bob -> Charlie: 5 BTC"})

	// 打印区块链
	blockchain.PrintBlockchain()
}

Block 0
Timestamp: 2025-01-20 15:00:00 +0800 CST
Transactions: [Genesis Block]
PrevBlockHash: 
Hash: 0
----------------------------
Block 1
Timestamp: 2025-01-20 15:00:01 +0800 CST
Transactions: [Alice -> Bob: 10 BTC]
PrevBlockHash: <hash-of-block-0>
Hash: <hash-of-block-1>
----------------------------
Block 2
Timestamp: 2025-01-20 15:00:02 +0800 CST
Transactions: [Bob -> Charlie: 5 BTC]
PrevBlockHash: <hash-of-block-1>
Hash: <hash-of-block-2>
----------------------------