我已经成功运行了React Native和web3@0.19.0两者rn-nodeify并ReactNativify成功运行.
我知道web3 v1.0会动态构建模块,但我想知道是否有人成功将web3@1.0.0集成到React Native中?
任何想法或建议将受到高度赞赏.
干杯!
我正在尝试使用 Angular 创建以太坊 dapp。我正在关注那篇文章:https :
//medium.com/blockchain-developer/learn-how-to-create-your-own-dapp-with-angular-9-part-iv-truffle-7704dc4269ab
但是,当我添加web3 to app with npm install --save web3,并在代码中调用它,我遇到了以下问题:
Error: ./node_modules/swarm-js/node_modules/eth-lib/lib/bytes.js
Module not found: Error: Can't resolve 'crypto' in '/home/szymon/dev/dapp/node_modules/swarm-js/node_modules/eth-lib/lib'
Error: ./node_modules/web3-eth-accounts/node_modules/eth-lib/lib/bytes.js
Module not found: Error: Can't resolve 'crypto' in '/home/szymon/dev/dapp/node_modules/web3-eth-accounts/node_modules/eth-lib/lib'
Error: ./node_modules/web3-eth-accounts/src/index.js
Module not found: Error: Can't resolve 'crypto' in '/home/szymon/dev/dapp/node_modules/web3-eth-accounts/src'
Error: ./node_modules/web3-providers-http/src/index.js
Module not found: Error: Can't resolve 'http' in '/home/szymon/dev/dapp/node_modules/web3-providers-http/src'
Error: ./node_modules/xhr2-cookies/dist/xml-http-request.js
Module not found: Error: Can't resolve 'http' in '/home/szymon/dev/dapp/node_modules/xhr2-cookies/dist'
Error: ./node_modules/web3-providers-http/src/index.js
Module not found: Error: Can't resolve 'https' …Run Code Online (Sandbox Code Playgroud) 我试图在我的ERC20令牌合同上调用一个方法.我正在连接到" https://rinkeby.infura.io/"httpProvider.我可以调用()常量方法,但是当我想通过调用send()函数来改变契约的状态时,我得到了这个提到的错误.如果您认为发布ABI JSON或Solidity合同有帮助,我也可以提供.我认为我的问题纯粹与web3有关.我想我需要签署交易(逻辑上),但web3文档没有提到任何内容.http://web3js.readthedocs.io/en/1.0/web3-eth-contract.html#methods-mymethod-send
这是我得到的错误:
Unhandled rejection Error: Invalid JSON RPC response: ""
at Object.InvalidResponse (/opt/backend/node_modules/web3-core-helpers/src/errors.js:42:16)
at XMLHttpRequest.request.onreadystatechange (/opt/backend/node_modules/web3-providers-http/src/index.js:60:32)
at XMLHttpRequestEventTarget.dispatchEvent (/opt/backend/node_modules/xhr2/lib/xhr2.js:64:18)
at XMLHttpRequest._setReadyState (/opt/backend/node_modules/xhr2/lib/xhr2.js:354:12)
at XMLHttpRequest._onHttpResponseEnd (/opt/backend/node_modules/xhr2/lib/xhr2.js:509:12)
at IncomingMessage.<anonymous> (/opt/backend/node_modules/xhr2/lib/xhr2.js:469:24)
at emitNone (events.js:111:20)
at IncomingMessage.emit (events.js:208:7)
at endReadableNT (_stream_readable.js:1055:12)
at _combinedTickCallback (internal/process/next_tick.js:138:11)
at process._tickCallback (internal/process/next_tick.js:180:9)
From previous event:
at PromiEvent (/opt/backend/node_modules/web3-core-promievent/src/index.js:35:24)
at send (/opt/backend/node_modules/web3-core-method/src/index.js:446:21)
at Object._executeMethod (/opt/backend/node_modules/web3-eth-contract/src/index.js:890:24)
at Object.currencyToken.sendSignUpBonousTokens (/opt/backend/server/common/token/currency-token.js:86:56)
at <anonymous>
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从调用此方法:
const Web3 = require('web3');
const Tx = require('ethereumjs-tx');
const …Run Code Online (Sandbox Code Playgroud) 我有一个节点js进程,它创建一个web3 websocket连接,如下所示:
web3 = new Web3('ws://localhost:7545')
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当进程完成时(我发送一个SIGTERM),它不会退出,而是永远挂起而没有控制台输出.
我注册了SIGINT和SIGTERM一个听众在什么处理过程中具有突出以观察process._getActiveRequests()和process._getActiveHandles(),我看到以下内容:
Socket {
connecting: false,
_hadError: false,
_handle:
TCP {
reading: true,
owner: [Circular],
onread: [Function: onread],
onconnection: null,
writeQueueSize: 0 },
<snip>
_peername: { address: '127.0.0.1', family: 'IPv4', port: 7545 },
<snip>
}
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为了完整性,这里是监听信号的代码:
async function stop() {
console.log('Shutting down...')
if (process.env.DEBUG) console.log(process._getActiveHandles())
process.exit(0)
}
process.on('SIGTERM', async () => {
console.log('Received SIGTERM')
await stop()
})
process.on('SIGINT', async () => {
console.log('Received SIGINT')
await stop()
})
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看起来web3正在打开一个套接字,这是有道理的,因为我从未告诉它关闭连接.通过文档和谷歌搜索,它看起来不像web3对象的close或end方法.
手动关闭stop …
我正在构建一个分散的应用程序,用户可以在其中将他们的加密货币钱包 (Metamask) 连接到我的网站。
They can initiate a connection request by clicking a button. On success, the wallet is connected and my website can interact with it.
Is there any way to initiate a disconnect request? Similar to a 'Log out' button. Currently, the users have to manually disconnect their wallet within Metamask settings which is not a straightforward process.
我正在构建一个为用户创建钱包的应用程序.一个选项是web3.py中的web3.personal API,它有一个newAccount('passphrase')方法.该方法仅返回已创建帐户的地址.
我正在寻找的是一个类似于web3.js中的eth.accounts API的函数,它有一个create([entropy])方法.它返回一个带有"地址"," 私钥 "和其他详细信息的帐户对象.
我对以太坊和这种开发实践的想法很新,所以很乐意从你那里得到一些帮助.先感谢您.
我正在尝试使用 uniswap 合约方法来简单地将 eth 交换为令牌,使用来自 metamask 钱包的 eth。Uniswap 合约方式为:
function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
external
payable
returns (uint[] memory amounts);
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我天真的印象是它应该看起来像这样,但我确信我遗漏了几个关键部分(例如签署交易,使用适当的回调方法),而且我找不到完整的综合示例。一个完整的工作示例应该是什么样的?
const ETHaddress = "0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2"
const DAIaddress = "0x6b175474e89094c44da98b954eedeac495271d0f"
const routerContract = new web3.eth.Contract(
UniswapRouterABI,
"0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D"
);
routerContract.methods.swapExactETHForTokens(500,[ETHaddress,DAIaddress],myWalletAddress,someDeadline)
.send(from: myWalletAddress, value: "1000000000000")
Run Code Online (Sandbox Code Playgroud) 我目前正在使用0.2xx版本的Web3 Javascript API.我通过创建智能合约(在REMIX IDE上)来部署我的自定义ERC20令牌.我安装了MetaMask并在https://wallet.ethereum.org/上进行了测试,将一些自定义ERC令牌发送到我的另一个帐户.它运作良好.我想在我的javascript代码中使用Web3添加"发送自定义ERC20令牌"功能.
这是我的代码如下.
var http = require('http');
var Web3 = require('web3');
var Tx = require('ethereumjs-tx');
var abi = [{"...."}];
var data = '0x00..';
var contract_addr = '0x00..';
var owner = '0x00..';
var web3 = new Web3(new Web3.providers.HttpProvider("https://ropsten.infura.io/"));
web3.eth.getBlock("latest", (error, result) => {
//console.log('error:', error);
//console.log('results', result);
});
var myContract = web3.eth.contract(abi);
var myContractInstance = myContract.at(address);
eb3.eth.getDefaultAccount = owner;
var defaultAccount = web3.eth.getDefaultAccount;
console.log('DefaultAccount => ', defaultAccount);
var total = myContractInstance.totalSupply();
var balance = myContractInstance.balanceOf(defaultAccount);
console.log('DefulatAccount total …Run Code Online (Sandbox Code Playgroud) 我正在尝试使用本地私钥在带有 web3.py 的 python 中发送 ERC20 令牌。
使用此代码,我可以发送以太:
w3 = Web3(HTTPProvider('https://api.myetherapi.com/eth'))
signed_txn = w3.eth.account.signTransaction(dict(
nonce=w3.eth.getTransactionCount(from_address),
gasPrice=w3.eth.gasPrice,
gas=100000,
to=to_address,
value=12345,
data=b'',
),
private_key,
)
w3.eth.sendRawTransaction(signed_txn.rawTransaction)
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然后我也发现了这个,但是估计Gas总是出错,在我看来,我无法像这样指定我发送的地址或通过某种签名证明它是我的地址?
contract = w3.eth.contract(address=address, abi=EIP20_ABI, bytecode=bytecode)
contract.functions.transfer(to_address, 121212).transact()
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所以我有 JSON abi、字节码、地址和我的私钥,我可以用我找到的代码以某种方式构建一个工作脚本吗?
提前致谢!
我想在 BNB 中计算 BEP20 代币的价格。我检查了 poocoin 和 pancakeswap 他们如何计算价格。正如我所见,他们通过 web3.js 不断调用 bsc-dataseed,但我还没有找到解决方案。
// Request params
{
"jsonrp": "2.0",
"method": "eth_blockNumber",
"params": [],
"id": 1
}
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{
"jsonrpc": "2.0",
"id": 53,
"method": "eth_call",
"params": [
{
"to": "0x1ee38d535d541c55c9dae27b12edf090c608e6fb",
"data": "0x252dba420000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000001c00000000000000000000000000000000000000000000000000000000000003800000000000000000000000000000000000000000000000000000000000000400000000000000000000000000000000000000000000000000000000000000048000000000000000000000000000000000000000000000000000000000000005000000000000000000000000000000000000000000000000000000000000000580000000000000000000000000000000000000000000000000000000000000060000000000000000000000000000000000000000000000000000000000000006800000000000000000000000000000000000000000000000000000000000000700000000000000000000000000000000000000000000000000000000000000078000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000880000000000000000000000000000000000000000000000000000000000000090000000000000000000000000000000000000000000000000000000000000009800000000000000000000000000000000000000000000000000000000000000a000000000000000000000000000000000000000000000000000000000000000a800000000000000000000000000000000000000000000000000000000000000b000000000000000000000000000000000000000000000000000000000000000b800000000000000000000000000000000000000000000000000000000000000c000000000000000000000000000000000000000000000000000000000000000c800000000000000000000000000000000000000000000000000000000000000d000000000000000000000000000000000000000000000000000000000000000d800000000000000000000000000000000000000000000000000000000000000e000000000000000000000000000000000000000000000000000000000000000e800000000000000000000000000000000000000000000000000000000000000f000000000000000000000000000000000000000000000000000000000000000f8000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000001080000000000000000000000000000000000000000000000000000000000000110000000000000000000000000003ff6c83226cdb10c7a42a2c54c67d63a135ab69000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000003fc20bdafdac6b2ae8f7f5f885f0819c2b968f0000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000008b018585d4949ae4714f057b66b8b033408bfa6000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000012c8db147721ac1e3e54e9ff73d99ef0ee4b1725000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000001b96b92314c44b159149f7e0303511fb2fc4774f000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000020bcc3b8a0091ddac2d0bc30f68e6cbb97de59cd000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000002c5d712cf39eaebc1ef2d1281eb48a70dcd34d49000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000003ab77e40340ab084c3e23be8e5a6f7afed9d41dc000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000003b872e6b1633f060680cf9c277b43dd1e254e564000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000056c77d59e82f33c712f919d09fceddf49660a829000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000006f656513f6e8eae19b6dc30cd372dd6ba4b5543a000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000070d8929d04b60af4fb9b58713ebcf18765ade422000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000007246d6ea86d34af343f03cc1eb952a4f98467a4e000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000007380e10f5c5f9dff4857de3cf9c39bb16f4c6dcf000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000007561eee90e24f3b348e1087a005f78b4c8453524000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000088c4bcf826410a81b58bc9b79a17641b443dc52e000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac0000000000000000000000000000000000000000000000000000000000000000000000000000000092ee07c591c26775b4d31259d5417e00553e857c000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac000000000000000000000000000000000000000000000000000000000000000000000000000000009adc6fb78cefa07e13e9294f150c1e8c1dd566c0000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000cc6b11de64dce6e5052a84b67cbbfd210ed530f7000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000d1f12370b2ba1c79838337648f820a87edf5e1e6000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000b3c4217ab2b265bf8c69718d280e3708b5e50577000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000b8875e207ee8096a929d543c9981c9586992eacb000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000c15fa3e22c912a276550f3e5fe3b0deb87b55acd000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000cee09ae86a78ce0cea3a4ea8cced5d41c0468e67000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000d9a0d1f5e02de2403f68bb71a15f8847a854b494000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000e7cc44de50b54906a9c1c48240650be2766481fc000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000fb7deb2236815222113d949d935cca4901531677000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000000000000000000000000000fa3107bca2ff6db4131bcd62b598cb00d9087f58000000000000000000000000000000000000000000000000000000000000004000000000000000000000000000000000000000000000000000000000000000040902f1ac00000000000000000000000000000000000000000000000000000000"
},
"latest"
]
}
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据我所知,这0x1ee38d535d541c55c9dae27b12edf090c608e6fb是一个包含multicall方法的合同。数据的前 10 个字符 (0x252dba42) 是aggregate方法。但是数据的剩余部分是什么?
这是aggregate方法的合同 ABI :
{
"constant": true,
"inputs": [
{
"components": [
{"name": "target","type": "address"},
{"name": "callData","type": "bytes"}
],
"name": "calls",
"type": …Run Code Online (Sandbox Code Playgroud) web3-donotuse ×10
ethereum ×8
javascript ×5
web3js ×3
blockchain ×2
erc20 ×2
python ×2
solidity ×2
angular ×1
bep20 ×1
metamask ×1
node.js ×1
react-native ×1
sign ×1
token ×1
websocket ×1