我正在尝试使用Web3将交易发送到以太坊区块链上。 web3的所有部分似乎都工作正常。
第一步需要“缓冲”节点包，以将私钥转换为某种“缓冲”格式。我无法终生获得Buffer来定义自己。我知道该缓冲区已安装在node_modules中，并且已将其包含在app.js和正在工作的节点控制器中。
var Buffer = require("buffer").Buffer;
还有其他原因使缓冲区保持未定义状态吗？
index.hbs
<h1>{{title}}</h1>
<p>Welcome to {{title}}</p>
<h2>Submit User Data</h2>
<form action="/addUser" method="post">
<p>User<br><input type="text" name="userName" value="" /></p>
<p>Address<br><input type="text" name="eth_address" value="" /></p>
<p>Data Array<br><textarea name="data_array"></textarea></p>
<input type="submit" value="Submit User Data">
</form>
<h2>List User Accounts</h2>
<table width="100%" cellpadding=10 cellborder=1>
{{#if msg includeZero=true}}
<span class='msg'>{{ msg }}</span>
{{/if}}
{{#each users}}
<tr>
<td><a href="/single/{{ id }}">{{userName}}</a></td>
<td>{{eth_address}}</td>
<td>{{data_array}}</td>
</tr>
{{/each}}
</table>
<p>Amount (Send Limit 100)<br><input type="text" name="amount"></p>
<p>To Address<br><input type="text" name="toAddress"></p>
<button id="send-token" name="submit">Send Token</button>
<div class="">Acct Balance: <span id="balance"></span></div>
<script>
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("https://mainnet.infura.io/v3/16aa8f4c7efc4ad3844ea4d8d1701554"));
}
var gasDefault = 2000000;
var fromAddress = '0x70362Ff8842c15B1c2ECD663BD7cCED0E366f0D6';
var fromPrivate = "censored";
web3.eth.defaultAccount = fromAddress;
var contractABI = [{"constant":true,"inputs":[],"name":"name","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_value","type":"uint256"}],"name":"approve","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"totalSupply","outputs":[{"name":"","type":"uint256"}],"payable":false,"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,"type":"function"},{"constant":true,"inputs":[],"name":"INITIAL_SUPPLY","outputs":[{"name":"","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"decimals","outputs":[{"name":"","type":"uint8"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_subtractedValue","type":"uint256"}],"name":"decreaseApproval","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"balanceOf","outputs":[{"name":"balance","type":"uint256"}],"payable":false,"type":"function"},{"constant":true,"inputs":[],"name":"symbol","outputs":[{"name":"","type":"string"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_to","type":"address"},{"name":"_value","type":"uint256"}],"name":"transfer","outputs":[{"name":"","type":"bool"}],"payable":false,"type":"function"},{"constant":false,"inputs":[{"name":"_spender","type":"address"},{"name":"_addedValue","type":"uint256"}],"name":"increaseApproval","outputs":[{"name":"success","type":"bool"}],"payable":false,"type":"function"},{"constant":true,"inputs":[{"name":"_owner","type":"address"},{"name":"_spender","type":"address"}],"name":"allowance","outputs":[{"name":"remaining","type":"uint256"}],"payable":false,"type":"function"},{"inputs":[],"payable":false,"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 contractAddress = "0x302cC16165B3AE82643aC62a8b77bA48b1f03fe1";
var daVinciContract = web3.eth.contract(contractABI);
var daVinci = daVinciContract.at(contractAddress);
var result = daVinci.balanceOf("0x70362Ff8842c15B1c2ECD663BD7cCED0E366f0D6",function(err, hash) {
if (!err)
$("#balance").text(hash.c[0]);
else
console.log(err);
});
// toAddress = 0x1E116fD224b9185dB17DC47AC32CA30A141F67aC
$(document).ready(function(){
$("#balance").text(result); // '0x25434534534'
// SEND TOKEN
$("#send-token").click(function(){
var amount = $("[name=amount]").val();
var toAddress = $("[name=toAddress]").val();
alert(toAddress);
if (toAddress !=='') {
if (amount !=='') {
if (amount > 100) {
alert("Too much to send");
} else {
// INTITIATE TRANSACTION
var count = web3.eth.getTransactionCount(fromAddress,function(err, hash) {
if (!err)
console.log(hash);
else
console.log(err);
});
// CREATE RAW TRANSACTION
var rawTransaction = {
"from": fromAddress, // Main account sending from
"nonce": web3.toHex(count),
"gasPrice": "0x04e3b29200",
"gasLimit": "0x7458",
"to": contractAddress,
"value": "0x0",
"data": daVinci.transfer.getData(toAddress, amount, {from: fromAddress})
};
var privKey = new Buffer(fromPrivate, 'hex');
var tx = new Tx(rawTransaction);
tx.sign(privKey);
var serializedTx = tx.serialize();
web3.eth.sendRawTransaction('0x' + serializedTx.toString('hex'), function(err, hash) {
if (!err)
console.log(hash);
else
console.log(err);
});
}
} else {
alert("Amount empty");
}
}
});
});
</script>
app.js
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var indexRouter = require('./routes/index');
var app = express();
// LOGGING
var logger = require('morgan');
// BODY POST PARSER
var bodyParser = require('body-parser')
app.use( bodyParser.json() ); // to support JSON-encoded bodies
app.use(bodyParser.urlencoded({ // to support URL-encoded bodies
extended: true
}));
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'hbs');
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', indexRouter);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
next(createError(404));
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
Indexcontroller.js
const express = require("express");
const con = require("../conn.js");
exports.indexView = (req, res) => {
// GET USER ACCOUNT LIST
var sql = "SELECT * FROM users";
var users = [];
con.query(sql, function (err, result) {
if (err) throw err;
var users = result;
res.render('index', {
title: 'Home Page',
users: users
});
});
};
答案 0 :(得分：1)
显然，您对代码不了解。模板文件中<script>标记中的Javascript在浏览器中运行。浏览器从您的node.js服务器下载呈现的HTML，然后解析该文件，然后运行浏览器中<script>标签中的Javascript。
浏览器中没有Buffer对象。
导致该错误的代码显然是设计为在node.js（而不是在浏览器中）中运行的，或者您缺少一些必须添加到浏览器以使其运行的环境，或者根本就没有设计过在其中运行浏览器。
您可能需要将该代码移至服务器，然后使用Ajax调用从您的网页访问服务器，以要求服务器运行该代码并返回结果。然后，有问题的代码将在设计运行的node.js以及内置的Buffer对象中运行。