WINDOWS中安裝WEB3始終不成功。

第一個坑，npm install web3 提示需要VC環境，安裝VC環境也有問題

網上各種找資料，都是介紹以下方法：

npm install windows-build-tools
沒有用。

最終解決方案為

npm install web3@^0.20.0
第二個坑，truffle部署的地址并不是testrpc中的account[0].其地址應該是truffle migrate時部署的地址。
testrpc中的accounts[0]

truffle migrate中的地址.如果這個地址找錯了，會讓web3找不到合約。

第三個坑。web3調用truffle部署好的合約后需要定義defaultAccount，否則會報invalid address錯誤而不能轉賬。查賬是沒有問題的。

const Base = require('./base.js');
var Web3 = require("web3");
//創建web3對象

// 連接到以太坊節點
if (typeof web3 !== 'undefined') {
web3 = new Web3(web3.currentProvider);
} else {
// set the provider you want from Web3.providers
web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));
}
var abi = [ { "constant": true, "inputs": [], "name": "name", "outputs": [ { "name": "", "type": "string" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": false, "inputs": [ { "name": "_spender", "type": "address" }, { "name": "_value", "type": "uint256" } ], "name": "approve", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "constant": true, "inputs": [], "name": "totalSupply", "outputs": [ { "name": "", "type": "uint256" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": false, "inputs": [ { "name": "_from", "type": "address" }, { "name": "_to", "type": "address" }, { "name": "_value", "type": "uint256" } ], "name": "transferFrom", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "constant": true, "inputs": [], "name": "INITIAL_SUPPLY", "outputs": [ { "name": "", "type": "uint256" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": true, "inputs": [], "name": "decimals", "outputs": [ { "name": "", "type": "uint8" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": false, "inputs": [ { "name": "_spender", "type": "address" }, { "name": "_subtractedValue", "type": "uint256" } ], "name": "decreaseApproval", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "constant": true, "inputs": [ { "name": "_owner", "type": "address" } ], "name": "balanceOf", "outputs": [ { "name": "balance", "type": "uint256" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": true, "inputs": [], "name": "symbol", "outputs": [ { "name": "", "type": "string" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "constant": false, "inputs": [ { "name": "_to", "type": "address" }, { "name": "_value", "type": "uint256" } ], "name": "transfer", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "constant": false, "inputs": [ { "name": "_spender", "type": "address" }, { "name": "_addedValue", "type": "uint256" } ], "name": "increaseApproval", "outputs": [ { "name": "", "type": "bool" } ], "payable": false, "stateMutability": "nonpayable", "type": "function" }, { "constant": true, "inputs": [ { "name": "_owner", "type": "address" }, { "name": "_spender", "type": "address" } ], "name": "allowance", "outputs": [ { "name": "", "type": "uint256" } ], "payable": false, "stateMutability": "view", "type": "function" }, { "inputs": [], "payable": false, "stateMutability": "nonpayable", "type": "constructor" }, { "anonymous": false, "inputs": [ { "indexed": true, "name": "owner", "type": "address" }, { "indexed": true, "name": "spender", "type": "address" }, { "indexed": false, "name": "value", "type": "uint256" } ], "name": "Approval", "type": "event" }, { "anonymous": false, "inputs": [ { "indexed": true, "name": "from", "type": "address" }, { "indexed": true, "name": "to", "type": "address" }, { "indexed": false, "name": "value", "type": "uint256" } ], "name": "Transfer", "type": "event" }];
var address ='0x3be29127330474399a7449b16a1ec01980e71690';
//通過abi以及合約部署的地址實例化一個coin
var coin = web3.eth.contract(abi).at(address);
//必須先定義defaultAccount，不然會報invalid address錯
web3.eth.defaultAccount= web3.eth.accounts[0];
module.exports = class extends Base {
async indexAction() {

console.log(web3.eth.defaultAccount);
this.assign('title11', web3.eth.coinbase);
await this.assign('xianjin',coin.balanceOf.call(web3.eth.coinbase));
// console.log(coin.balanceOf(web3.eth.accounts[1]));
// coin.transferFrom(web3.eth.accounts[0],web3.eth.accounts[1], 800);
coin.transfer(web3.eth.accounts[1],200);
// console.log(web3.eth.accounts[1]);
return this.display();
}
};

上面是thinkjs的一個controller 調用web3進行查賬，轉賬200個幣到accounts[1]

轉載于:https://www.cnblogs.com/xiaocongcong888/p/9497853.html

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