大神您好,使用webpack+truffle官方的box # MetaCoin学习,部署合约到测试网后,电脑上运行一切正常,然后用手机钱包打开发现token转账后状态不更新。 也就是执行index.js的sendCoin函数 await sendCoin(receiver, amount).send({ from: this.account }); 这段语句后面的代码没有执行(去钱包查询确实转账成功了),不知道是处理,求解答,谢谢! 以下是合约文件:
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "./ConvertLib.sol";
// This is a simple example of a coin-like contract.
// It is not standards compatible and cannot be expected to talk to other
// coin/token contracts. If you want to create a standards-compliant
// token, see: https://github.com/ConsenSys/Tokens. Cheers!
contract MetaCoin {
mapping (address => uint) balances;
event Transfer(address indexed _from, address indexed _to, uint256 _value);
constructor() public {
balances[msg.sender] = 10000;
}
function sendCoin(address receiver, uint amount) public returns(bool sufficient) {
if (balances[msg.sender] < amount) return false;
balances[msg.sender] -= amount;
balances[receiver] += amount;
emit Transfer(msg.sender, receiver, amount);
return true;
}
function getBalanceInEth(address addr) public view returns(uint) {
return ConvertLib.convert(getBalance(addr),2);
}
function getBalance(address addr) public view returns(uint) {
return balances[addr];
}
}
下面是index.js:
import Web3 from "web3";
import metaCoinArtifact from "../../build/contracts/MetaCoin.json";
const App = {
web3: null,
account: null,
meta: null,
start: async function() {
const { web3 } = this;
try {
// get contract instance
const networkId = await web3.eth.net.getId();
const deployedNetwork = metaCoinArtifact.networks[networkId];
this.meta = new web3.eth.Contract(
metaCoinArtifact.abi,
deployedNetwork.address,
);
// get accounts
const accounts = await web3.eth.getAccounts();
this.account = accounts[0];
this.refreshBalance();
} catch (error) {
console.error("Could not connect to contract or chain.");
}
},
refreshBalance: async function() {
const { getBalance } = this.meta.methods;
const balance = await getBalance(this.account).call();
const balanceElement = document.getElementsByClassName("balance")[0];
balanceElement.innerHTML = balance;
},
sendCoin: async function() {
const amount = parseInt(document.getElementById("amount").value);
const receiver = document.getElementById("receiver").value;
this.setStatus("Initiating transaction... (please wait)");
const { sendCoin } = this.meta.methods;
await sendCoin(receiver, amount).send({ from: this.account });
this.setStatus("Transaction complete!");
this.refreshBalance();
},
setStatus: function(message) {
const status = document.getElementById("status");
status.innerHTML = message;
},
};
window.App = App;
window.addEventListener("load", function() {
if (window.ethereum) {
// use MetaMask's provider
App.web3 = new Web3(window.ethereum);
window.ethereum.enable(); // get permission to access accounts
} else {
console.warn(
"No web3 detected. Falling back to http://127.0.0.1:8545. You should remove this fallback when you deploy live",
);
// fallback - use your fallback strategy (local node / hosted node + in-dapp id mgmt / fail)
App.web3 = new Web3(
new Web3.providers.HttpProvider("http://127.0.0.1:8545"),
);
}
App.start();
});