标签: ethereum

我需要像这样转换以太坊地址

0xB34080739D5B656D76089f9f21b374BA5dafA373

像这样的公钥

e2d3a3a43e71eb541e12504cee22ed74024969b46b9e68ea7f9e5384fe96fc04

我是这样得到地址的

from web3 import Web3

w3 = Web3(Web3.HTTPProvider('https://sokol.poa.network'))

addr = w3.toHex(w3.sha3(text=public_key)[12:])

也许有一个图书馆可以做到这一点？请帮忙

我们可以将资金从地址（此）转移到收件人。但是有没有什么方法可以将资金直接从 msg.sender 钱包转移到收件人呢？我无法在调用 payoutBonus 调用时设置 msg.value。因为我只能在 payoutBonus 方法中获得金额。

function payoutBonus(address recipient) public payable returns (bool) {
    // bonus = calculateBonus();
    //transfer this bonus to recipient from msg.sender;
    return true;
}

我正在开发一个带有 webpack 的小型 Dapp 和基于 Web 组件（lit-library）的 UI。为了捆绑文件，我使用 webpack 和 webpack-dev-server 来刷新页面。一切对我来说都很好。

现在，我尝试使用 web3 与我的智能合约交互，但是当我导入 web3 并从中创建一个新实例时，出现以下错误：

    Uncaught Error: Cannot find module 'http'
    webpackMissingModule xml-http-request.js:21
    js xml-http-request.js:21
    Webpack 14
xml-http-request.js:21:19
    webpackMissingModule xml-http-request.js:21
    js xml-http-request.js:21
    Webpack 14
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__
        <anonymous>
        <anonymous>
        <anonymous>

此错误出现在我的 Firefox 的控制台中。

包.json

    Uncaught Error: Cannot find module 'http'
    webpackMissingModule xml-http-request.js:21
    js xml-http-request.js:21
    Webpack 14
xml-http-request.js:21:19
    webpackMissingModule xml-http-request.js:21
    js xml-http-request.js:21
    Webpack 14
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__
        js
        __webpack_require__ …

我正在用 React 构建一个简单的应用程序，但是var manager = wait lottery.methods.manager().call(); 永远不会检索值，我怎么会错呢？

彩票.js

import web3 from './web3';

const address = '0x430b45dcf781d58e73CeeA288b4196B6ddeE4d7E';

const abi = [{"inputs":[],"stateMutability":"nonpayable","type":"constructor"},{"inputs":[],"name":"enter","outputs":[],"stateMutability":"payable","type":"function"},{"inputs":[],"name":"getPlayers","outputs":[{"internalType":"address[]","name":"","type":"address[]"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"manager","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"pickWinner","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"","type":"uint256"}],"name":"players","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"random","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"}];
const cont = new web3.eth.Contract(abi,address);
export default cont;

应用程序.js

import React,{Component} from 'react';
import logo from './logo.svg';
import './App.css';
import web3 from './web3';
import lottery from './lottery';

class App extends Component {
  
  constructor (props){
    super(props);
    this.state = {"manager":''};
  }

  async componentDidMount(){
    console.log("componentDidMount fired");
    var manager = await lottery.methods.manager().call();//never set  manager var
    this.setState({manager});
  }

  render() {
    return (
      <div> …

我在 Ropsten 以太坊测试网络上部署了以下智能合约，之后我尝试使用 @alch/alchemy-web3 npm 包进行交易（是的，我正在使用 Alchemy API），但正如你所看到的，我在交易中收取了费用。这是为什么？公共视图函数调用不应该花费 0 Gas 吗？

部署的智能合约

// SPDX-Lincense-Identifier: MIT\npragma solidity ^0.8.11;\n\ncontract VendingMachine {\n    address public owner;\n    mapping(address => uint256) public donutBalances;\n\n    constructor() {\n        owner = msg.sender;\n        donutBalances[address(this)] = 100;\n    }\n\n    function getVendingMachineBalance() public view returns (uint256) {\n        return donutBalances[address(this)];\n    }\n\n    function restock(uint amount) public {\n        require(msg.sender == owner, "Only the owner can restock this machine.");\n        donutBalances[address(this)] += amount;\n    }\n\n    function purchase(uint amount) public payable {\n        require(msg.sender == owner, "Only the owner can …

如何覆盖 Opezeppelin 默认小数点 18。文档说 _setupDecimals() 应该从构造函数调用；我究竟做错了什么。

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.4;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

contract MyToken is ERC20 {

    uint8 _decimals;

    constructor() ERC20("MyToken", "MTK") {

         _decimals = 3;

         function _setupDecimals(uint8 decimals_) internal {
            _decimals = decimals_;
         }

        _mint(msg.sender, 5000 * 10 ** decimals());

    }
}

我们可以像数据库一样使用以太坊网络来存储数据吗？如果将其用作数据库，可能会出现哪些问题。

我在将 web3 导入到 ReactJS 时遇到问题。要复制我的问题，请初始化一个新的反应应用程序

npx create-react-app my-app
cd my-app

然后在此位置打开终端。写：

npm install web3
npm install

在 App,js 文件中添加以下行

import Web3 from "web3"; 

我在执行此操作后收到错误，npm start然后收到未解决的错误，即

找不到模块：错误：无法解析“流”

找不到模块：错误：无法解析“加密”

我尝试在网上寻找解决方案，特别是我尝试了以下每个

1. 如何在 webpack 5 中 Polyfill 节点核心模块
2. https://www.youtube.com/watch?v=u1PPNIBvQjk
3. 导入 web3 导致 React js 出现问题
4. https://github.com/facebook/create-react-app/issues/11756#issuecomment-1001162736
5. https://namespaceit.com/blog/how-fix-writing-change-webpack-5-used-to-include-polyfills-for-nodejs-core-modules-by-default-error
6. 如何使用 create-react-app 创建 React App 包括 Web3？我收到模块未找到错误。重大变更：使用了 webpack < 5

似乎没有人适合我。对于如何解决这个问题有什么建议吗？谢谢你！

我有网络应用程序,企业应用程序的背景.有了这样的背景; 我在哪里适合区块链!什么是最简单的术语!