不检索值--简单彩票合同管理方法

Question

我正在用react构建一个简单的应用程序，但是lottery.methods.manager().call(); var管理器= var manager =等待永远不会检索值，我怎么可能会出错呢？

lottery.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;

App.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>
        <h2>Lottery contract</h2>
        <p>This contract is managed by {this.state.manager}</p>
      </div>
    );
  }
}

export default App;

web3.js

import Web3 from "web3";

const web3 = new Web3(window.ethereum);//Web3(window.web3.currentProvider);


export default web3;

​

​

请给我任何建议，谢谢。

Answer 1

对我起作用的是在https://remix.ethereum.org/上编译我的合同，并从那里复制abi。

​

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"
    }
];

​

Answer 2

那里。

我一直在寻找继续这个培训项目，很多时候，我认为我有一些配置不好的方式，我测试了我所使用的每一种技术。在测试的最后，元问题扩展，我发现我的元问题有问题，好吧，我卸载，然后重新安装它。沃拉。这是工作。

对不起，如果我不能说一些技术细节，但我的信息有类似问题的人，它没有给up...hahaha

​

​

Answer 3

塞巴的回答是什么对我有用。使用Remix在线编辑器编译和部署。然后，您可以复制有效的abi。