Infura 可以做什么？

1. 向以太坊网络发送交易并获取交易的结果

const Web3 = require('web3');
const Tx = require('ethereumjs-tx').Transaction;const RPC_ENDPOINT = 'https://ropsten.infura.io/v3/YOUR_INFURA_PROJECT_ID';
const PRIVATE_KEY = 'YOUR_PRIVATE_KEY';const web3 = new Web3(new Web3.providers.HttpProvider(RPC_ENDPOINT));// 构建交易对象
const txObj = {nonce: web3.utils.toHex(await web3.eth.getTransactionCount(MY_ADDR)),to: TO_ADDR,value: web3.utils.toHex(web3.utils.toWei('0.01', 'ether')),gasLimit: web3.utils.toHex(21000),gasPrice: web3.utils.toHex(await web3.eth.getGasPrice())
};// 签名交易
const privateKey = Buffer.from(PRIVATE_KEY, 'hex');
const tx = new Tx(txObj, { 'chain': 'ropsten' });
tx.sign(privateKey);
const serializedTx = tx.serialize().toString('hex');// 发送交易
const receipt = await web3.eth.sendSignedTransaction('0x' + serializedTx);
console.log('Transaction hash:', receipt.transactionHash);
console.log('Transaction receipt:', receipt);

上述代码首先使用Web3和ethereumjs-tx库进行交易构建和签名，然后使用Infura发送已签名的交易并等待交易收据。交易收据包含有关交易状态和相关信息的重要信息，例如交易哈希值、交易费用和交易状态等。可以使用这些信息对自己的应用程序进行处理和存储。

2. 获取以太坊地址的余额、交易历史记录等信息

获取余额

const Web3 = require('web3');
const web3 = new Web3('https://mainnet.infura.io/v3/<YOUR PROJECT ID>');const address = '0x123456...'; // 替换为您要查询的地址
web3.eth.getBalance(address, (err, balance) => {if (err) {console.error(err);} else {console.log(`Address ${address} has a balance of ${web3.utils.fromWei(balance, 'ether')} ETH`);}
});

获取交易历史记录

const Web3 = require('web3');
const web3 = new Web3('https://mainnet.infura.io/v3/<YOUR PROJECT ID>');const address = '0x123456...'; // 替换为您要查询的地址
web3.eth.getTransactionsByAddress(address, (err, txs) => {if (err) {console.error(err);} else {console.log(`Address ${address} has ${txs.length} transactions:`);txs.forEach((tx) => console.log(`Transaction hash: ${tx.hash}`));}
});

注意:Infura需要您注册并获得项目ID才能使用。将代码中的替换为您自己的项目ID。

3. 通过 Web3.js 等以太坊库与智能合约进行交互

创建web3.js实例

   const Web3 = require('web3');const infuraKey = '<Infura API Key>';const infuraEndpoint = 'https://mainnet.infura.io/v3/' + infuraKey;const provider = new Web3.providers.HttpProvider(infuraEndpoint);const web3 = new Web3(provider);

获取智能合约实例

   const abi = <智能合约ABI>;const contractAddress = '<智能合约地址>';const contract = new web3.eth.Contract(abi, contractAddress);

调用智能合约方法

   const methodName = '<智能合约方法名>';const methodArgs = [<参数1>, <参数2>, ...];const txOptions = {from: '<发送方地址>',gas: '<Gas上限>',gasPrice: '<Gas价格>',};const result = await contract.methods[methodName](...methodArgs).send(txOptions);

完整代码

const Web3 = require('web3');
const infuraKey = '<Infura API Key>';
const infuraEndpoint = 'https://mainnet.infura.io/v3/' + infuraKey;
const provider = new Web3.providers.HttpProvider(infuraEndpoint);
const web3 = new Web3(provider);const abi = <智能合约ABI>;
const contractAddress = '<智能合约地址>';
const contract = new web3.eth.Contract(abi, contractAddress);const methodName = '<智能合约方法名>';
const methodArgs = [<参数1>, <参数2>, ...];
const txOptions = {from: '<发送方地址>',gas: '<Gas上限>',gasPrice: '<Gas价格>',
};
const result = await contract.methods[methodName](...methodArgs).send(txOptions);

3. 使用 Infura 发送以太币

首先，您需要在 Infura 上注册一个账号并获取一个 API 密钥。然后使用 Web3.js 库与 Infura 进行交互。

const Web3 = require('web3');// 连接到以太坊网络
const web3 = new Web3(new Web3.providers.HttpProvider('https://mainnet.infura.io/v3/your-project-id'));// 发送以太币
const sendTransaction = async () => {const account = '0xYourAccountAddress';const privateKey = '0xYourPrivateKey';const toAddress = '0xRecipientAddress';const value = '1000000000000000000'; // 1 ETHconst gasPrice = await web3.eth.getGasPrice();const gasLimit = '21000';const nonce = await web3.eth.getTransactionCount(account);const transaction = {from: account,to: toAddress,value: value,gasPrice: gasPrice,gas: gasLimit,nonce: nonce};const signedTransaction = await web3.eth.accounts.signTransaction(transaction, privateKey);const transactionReceipt = await web3.eth.sendSignedTransaction(signedTransaction.rawTransaction);console.log(transactionReceipt);
};sendTransaction();