使用 web3.js 库调用智能合约方法

Question

我是 web3.js 的新手，我正在尝试从 omesigo 智能合约调用一个方法，但我遇到了一个令人困惑的错误。我已经阅读过 web3 文档并尝试过。

package.json

{
  "name": "web3-learn",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "@babel/runtime": "^7.3.1",
    "babel-cli": "^6.26.0",
    "web3": "^1.0.0-beta.38"
  }
}

node version: 10.15.0

index.js 相关行：

let contract = web3.eth.Contract(abi, address);
contract.methods.name().call((err, res) => {console.log(res)});

/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/@babel/runtime/helpers/nonIterableSpread.js:2
  throw new TypeError("Invalid attempt to spread non-iterable instance");
  ^

TypeError: Invalid attempt to spread non-iterable instance
    at _nonIterableSpread (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/@babel/runtime/helpers/nonIterableSpread.js:2:9)
    at _toConsumableArray (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/@babel/runtime/helpers/toConsumableArray.js:8:60)
    at CallContractMethod.set (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/web3-core-method/dist/web3-core-method.cjs.js:405:34)
    at MethodsProxy.executeMethod (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/web3-eth-contract/dist/web3-eth-contract.cjs.js:525:26)
    at Function.anonymousFunction.(anonymous function) [as call] (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/node_modules/web3-eth-contract/dist/web3-eth-contract.cjs.js:497:27)
    at Object.<anonymous> (/home/amin/Documents/projects/solidity-workshop/solidity-learn/src/web3-learn/index.js:34:25)
    at Module._compile (internal/modules/cjs/loader.js:689:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
    at Module.load (internal/modules/cjs/loader.js:599:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
    at Function.Module._load (internal/modules/cjs/loader.js:530:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:742:12)
    at startup (internal/bootstrap/node.js:283:19)
    at bootstrapNodeJSCore (internal/bootstrap/node.js:743:3)

它应该打印 Omisego 代币名称。预先感谢您的帮助。

Answer 1

我遇到了同样的错误，通过将 Web3 库升级到 "web3": "^1.0.0-beta.39"

解决了这个问题

深入分析错误，似乎与contract.method arguments的深度克隆有关。经过几个小时无果而终的调试后，我偶然发现了 Web3 版本，发现它是 beta.39 的特色版本。（一天前发布）

Answer 2

我一直面临同样的问题，与您的方法唯一不同的是 web3 api 的版本，对我来说是 1.0.0-beta.46。问题的解决似乎有些牵强。

使用 web3.js 库调用智能合约方法

Calling a smart contract method using web3.js library

javascript

ethereum

solidity

smartcontracts