是否可以在 ERC721 合约中调用 ERC20 function？

Question

What I am trying to achieve is calling a transferFrom from ERC20 contract inside a ERC721 contract like this:

My ERC20 contract:

pragma solidity ^0.7.0;
import "../openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
import "../openzeppelin-contracts/contracts/math/SafeMath.sol";

contract ERC20Token is IERC20 {
  using SafeMath for uint256;
  bytes32[] public candidateList;
   
  uint public totalTokens;
  uint public balanceTokens;
  uint public tokenPrice;
   
  // what is the voter address?
  // total tokens purchased
  // tokens voted per candidate 
   
  struct voter {
    address voterAddress;
    uint tokensBought;
    uint256[] tokensUsedPerCandidate;
  }
   
  mapping(address => voter) public voterInfo;
   
  mapping(bytes32 => uint256) public votesReceived;

  string public symbol;
  string public  name;
  uint8 public decimals;

  mapping(address => uint256) balances;
  mapping(address => mapping(address => uint256)) allowed;
  
  constructor(uint256 _totalTokens, uint256 _tokenPrice, bytes32[] memory _candidateNames)  {
    symbol = "NCToken";
    name = "NCSOFT TOKEN";
    decimals = 0;
    totalTokens = _totalTokens;
    balanceTokens = _totalTokens;
    tokenPrice = _tokenPrice;
    candidateList = _candidateNames;
    emit Transfer(address(0), msg.sender, totalTokens);


   function transferFrom(address from, address to, uint256 tokens) public override returns (bool) { //This is the function I am  trying to call from ERC721 contract
        balances[from] = SafeMath.sub(balances[from], tokens);
        allowed[from][msg.sender] = SafeMath.sub(allowed[from][msg.sender], tokens);
        balances[to] = SafeMath.add(balances[to], tokens);
        emit Transfer(from, to, tokens);
        return true;
    }

}

My ERC721 contract:

// SPDX-License-Identifier: MIT
pragma solidity ^0.7.0;

import "../openzeppelin-contracts/contracts/token/ERC721/IERC721.sol";
import "../openzeppelin-contracts/contracts/token/ERC721/ERC721.sol";
import "../openzeppelin-contracts/contracts/token/ERC721/IERC721Receiver.sol";
import "../openzeppelin-contracts/contracts/math/SafeMath.sol";
import "../openzeppelin-contracts/contracts/utils/Address.sol";
import "../openzeppelin-contracts/contracts/utils/Counters.sol";
import "./ERC20Token.sol";

contract NFTtoken is ERC721 {
    using SafeMath for uint256;
    using Address for address;
    using Counters for Counters.Counter;
    Counters.Counter private _tokenIds;
   
    bytes32[] candidates = [bytes32('Rama'), bytes32('Nick'), bytes32('Jose')];
    ERC20Token ERC20TokenContract = new ERC20Token(1000, 1, candidates); //instantiating an ERC20 contract
    

    address payable public owner;
    mapping(bytes4 => bool) supportedInterfaces;

    mapping(uint256 => address) tokenOwners; //a mapping from NFT ID to the address that owns it
    mapping(address => uint256) balances; //a mapping from NFT ID to the address that owns it 
    mapping(uint256 => address) allowance; //a mapping from NFT ID to approved address
    mapping(address => mapping(address => bool)) operators; //Mapping from owner address to mapping of operator addresses.
   // mapping (uint256 => string) idToUri;
    uint8 public decimals;

    uint256[] public allValidTokenIds;
    mapping(uint256 => uint256) private allValidTokenIndex;
    string[] public allNFTNames;

    struct NFT {
        //uint NFTID;
        string name;
        address creator;
    }

    mapping(address => NFT) public nftInfo;


    constructor() ERC721("NC NFT example", "NCNFT") {
        owner = msg.sender;
        decimals = 0;
    }


    function mint(string calldata nftName) external payable {
        uint256 newItemId = _tokenIds.current();
        _mint(msg.sender, newItemId);

        nftInfo[msg.sender].name = nftName;
        nftInfo[msg.sender].creator = msg.sender;

        allValidTokenIndex[newItemId] = allValidTokenIds.length;
        allValidTokenIds.push(newItemId);
        _tokenIds.increment();
    }

    function transferNFT(address from, address to, uint256 tokenId)  public returns (bool){
        transferFrom(from, to, tokenId);
        ERC20TokenContract.transferFrom(to, nftInfo[from].creator, 10); 
//<-----***********This is throwing an error! I am trying to call ERC20Token.transferFrom. 
    }

    function allNFTs() public view returns (uint256[] memory) {
        return allValidTokenIds;
    }
}

Error Message when transferNFT from ERC721 is called.

MetaMask - RPC Error: [ethjs-query] while formatting outputs from RPC '{"value":{"code":-32603,"data":{"message":"VM Exception while processing transaction: revert ERC721: operator query for nonexistent token","code":-32000,"data":{"0x0b5d04087c39a8caa2f730815e42f619d33c9d0c3b8682c8c01d3f1ecf0e7d0f":{"error":"revert","program_counter":7889,"return":"0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002c4552433732313a206f70657261746f7220717565727920666f72206e6f6e6578697374656e7420746f6b656e0000000000000000000000000000000000000000","reason":"ERC721: operator query for nonexistent token"},"stack":"RuntimeError: VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\n    at Function.RuntimeError.fromResults (C:\\Program Files\\WindowsApps\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\app\\resources\\static\\node\\node_modules\\ganache-core\\lib\\utils\\runtimeerror.js:94:13)\n    at BlockchainDouble.processBlock (C:\\Program Files\\WindowsApps\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\app\\resources\\static\\node\\node_modules\\ganache-core\\lib\\blockchain_double.js:627:24)\n    at runMicrotasks (<anonymous>)\n    at processTicksAndRejections (internal/process/task_queues.js:93:5)","name":"RuntimeError"}}}}' 
{code: -32603, message: `[ethjs-query] while formatting outputs from RPC '{…/task_queues.js:93:5)","name":"RuntimeError"}}}}'`}
code: -32603
message: "[ethjs-query] while formatting outputs from RPC '{\"value\":{\"code\":-32603,\"data\":{\"message\":\"VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\",\"code\":-32000,\"data\":{\"0x0b5d04087c39a8caa2f730815e42f619d33c9d0c3b8682c8c01d3f1ecf0e7d0f\":{\"error\":\"revert\",\"program_counter\":7889,\"return\":\"0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002c4552433732313a206f70657261746f7220717565727920666f72206e6f6e6578697374656e7420746f6b656e0000000000000000000000000000000000000000\",\"reason\":\"ERC721: operator query for nonexistent token\"},\"stack\":\"RuntimeError: VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\n    at Function.RuntimeError.fromResults (C:\\\\Program Files\\\\WindowsApps\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\app\\\\resources\\\\static\\\\node\\\\node_modules\\\\ganache-core\\\\lib\\\\utils\\\\runtimeerror.js:94:13)\\n    at BlockchainDouble.processBlock (C:\\\\Program Files\\\\WindowsApps\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\app\\\\resources\\\\static\\\\node\\\\node_modules\\\\ganache-core\\\\lib\\\\blockchain_double.js:627:24)\\n    at runMicrotasks (<anonymous>)\\n    at processTicksAndRejections (internal/process/task_queues.js:93:5)\",\"name\":\"RuntimeError\"}}}}'"
[[Prototype]]: Object

localhost/:1 Uncaught (in promise) 
{code: -32603, message: `[ethjs-query] while formatting outputs from RPC '{…/task_queues.js:93:5)","name":"RuntimeError"}}}}'`, stack: '{\n  "code": -32603,\n  "message": "[ethjs-query] wh…gaeaoehlefnkodbefgpgknn/background-0.js:1:216902)'}
code: -32603
message: "[ethjs-query] while formatting outputs from RPC '{\"value\":{\"code\":-32603,\"data\":{\"message\":\"VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\",\"code\":-32000,\"data\":{\"0x0b5d04087c39a8caa2f730815e42f619d33c9d0c3b8682c8c01d3f1ecf0e7d0f\":{\"error\":\"revert\",\"program_counter\":7889,\"return\":\"0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002c4552433732313a206f70657261746f7220717565727920666f72206e6f6e6578697374656e7420746f6b656e0000000000000000000000000000000000000000\",\"reason\":\"ERC721: operator query for nonexistent token\"},\"stack\":\"RuntimeError: VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\n    at Function.RuntimeError.fromResults (C:\\\\Program Files\\\\WindowsApps\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\app\\\\resources\\\\static\\\\node\\\\node_modules\\\\ganache-core\\\\lib\\\\utils\\\\runtimeerror.js:94:13)\\n    at BlockchainDouble.processBlock (C:\\\\Program Files\\\\WindowsApps\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\app\\\\resources\\\\static\\\\node\\\\node_modules\\\\ganache-core\\\\lib\\\\blockchain_double.js:627:24)\\n    at runMicrotasks (<anonymous>)\\n    at processTicksAndRejections (internal/process/task_queues.js:93:5)\",\"name\":\"RuntimeError\"}}}}'"
stack: "{\n  \"code\": -32603,\n  \"message\": \"[ethjs-query] while formatting outputs from RPC '{\\\"value\\\":{\\\"code\\\":-32603,\\\"data\\\":{\\\"message\\\":\\\"VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\\",\\\"code\\\":-32000,\\\"data\\\":{\\\"0x0b5d04087c39a8caa2f730815e42f619d33c9d0c3b8682c8c01d3f1ecf0e7d0f\\\":{\\\"error\\\":\\\"revert\\\",\\\"program_counter\\\":7889,\\\"return\\\":\\\"0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002c4552433732313a206f70657261746f7220717565727920666f72206e6f6e6578697374656e7420746f6b656e0000000000000000000000000000000000000000\\\",\\\"reason\\\":\\\"ERC721: operator query for nonexistent token\\\"},\\\"stack\\\":\\\"RuntimeError: VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\\\n    at Function.RuntimeError.fromResults (C:\\\\\\\\Program Files\\\\\\\\WindowsApps\\\\\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\\\\\app\\\\\\\\resources\\\\\\\\static\\\\\\\\node\\\\\\\\node_modules\\\\\\\\ganache-core\\\\\\\\lib\\\\\\\\utils\\\\\\\\runtimeerror.js:94:13)\\\\n    at BlockchainDouble.processBlock (C:\\\\\\\\Program Files\\\\\\\\WindowsApps\\\\\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\\\\\app\\\\\\\\resources\\\\\\\\static\\\\\\\\node\\\\\\\\node_modules\\\\\\\\ganache-core\\\\\\\\lib\\\\\\\\blockchain_double.js:627:24)\\\\n    at runMicrotasks (<anonymous>)\\\\n    at processTicksAndRejections (internal/process/task_queues.js:93:5)\\\",\\\"name\\\":\\\"RuntimeError\\\"}}}}'\",\n  \"stack\": \"Error: [ethjs-query] while formatting outputs from RPC '{\\\"value\\\":{\\\"code\\\":-32603,\\\"data\\\":{\\\"message\\\":\\\"VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\\",\\\"code\\\":-32000,\\\"data\\\":{\\\"0x0b5d04087c39a8caa2f730815e42f619d33c9d0c3b8682c8c01d3f1ecf0e7d0f\\\":{\\\"error\\\":\\\"revert\\\",\\\"program_counter\\\":7889,\\\"return\\\":\\\"0x08c379a00000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000000000002c4552433732313a206f70657261746f7220717565727920666f72206e6f6e6578697374656e7420746f6b656e0000000000000000000000000000000000000000\\\",\\\"reason\\\":\\\"ERC721: operator query for nonexistent token\\\"},\\\"stack\\\":\\\"RuntimeError: VM Exception while processing transaction: revert ERC721: operator query for nonexistent token\\\\n    at Function.RuntimeError.fromResults (C:\\\\\\\\Program Files\\\\\\\\WindowsApps\\\\\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\\\\\app\\\\\\\\resources\\\\\\\\static\\\\\\\\node\\\\\\\\node_modules\\\\\\\\ganache-core\\\\\\\\lib\\\\\\\\utils\\\\\\\\runtimeerror.js:94:13)\\\\n    at BlockchainDouble.processBlock (C:\\\\\\\\Program Files\\\\\\\\WindowsApps\\\\\\\\GanacheUI_2.5.4.0_x64__5dg5pnz03psnj\\\\\\\\app\\\\\\\\resources\\\\\\\\static\\\\\\\\node\\\\\\\\node_modules\\\\\\\\ganache-core\\\\\\\\lib\\\\\\\\blockchain_double.js:627:24)\\\\n    at runMicrotasks (<anonymous>)\\\\n    at processTicksAndRejections (internal/process/task_queues.js:93:5)\\\",\\\"name\\\":\\\"RuntimeError\\\"}}}}'\\n    at new i (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:148782)\\n    at s (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:146325)\\n    at Object.internal (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:146935)\\n    at y.<anonymous> (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:210928)\\n    at Object.h (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:35204)\\n    at u (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:1:117610)\\n    at y.a.emit (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:1:118146)\\n    at y._setTransactionStatus (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-1.js:1:46740)\\n    at y.setTxStatusFailed (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-1.js:1:45972)\\n    at B._failTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:225990)\\n    at B.approveTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:217659)\\n    at async B.updateAndApproveTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:216902)\"\n}\n  at new i (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:148782)\n  at s (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:146325)\n  at Object.internal (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:146935)\n  at y.<anonymous> (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:210928)\n  at Object.h (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:18:35204)\n  at u (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:1:117610)\n  at y.a.emit (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/common-0.js:1:118146)\n  at y._setTransactionStatus (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-1.js:1:46740)\n  at y.setTxStatusFailed (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-1.js:1:45972)\n  at B._failTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:225990)\n  at B.approveTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:217659)\n  at async B.updateAndApproveTransaction (chrome-extension://nkbihfbeogaeaoehlefnkodbefgpgknn/background-0.js:1:216902)"
[[Prototype]]: Object
setTimeout (async)      
(anonymous) @   inpage.js:1
write   @   inpage.js:1

This is my javascript file calling the functions from both contracts.

// Import libraries we need.
import { default as Web3} from 'web3';
import { default as contract } from 'truffle-contract'

import voting_artifacts from '../../build/contracts/Voting.json'
import voting_artifacts2 from '../../build/contracts/DeedToken.json'

window.App = {
 start: function() {
  var self = this;
  self.transferNFT();
 },
transferNFT: function() {
  NFTContract.deployed().then(function(contractInstance) {
    let toAddress = $("#to-address").val();
    let NFTid_temp = $("#nft-id").val();
    let NFTid = NFTid_temp.substring(7);
    contractInstance.transferFrom(web3.currentProvider.selectedAddress, toAddress, NFTid, {gas: 140000, from: web3.eth.accounts[0]});
  })
}
}

window.addEventListener('load', async function() {
 if (window.ethereum) {
   await window.ethereum.send('eth_requestAccounts');
   window.web3 = new Web3(window.ethereum);
 }
 else {
  console.warn("No web3 detected.");
  window.web3 = new Web3(new Web3.providers.HttpProvider("http://127.0.0.1:8545"));
 }

 App.start();
});

Answer 1

You could use the interface if you do not want the full functionality of the contract.

openzeppelin IERC20

You copy full code in your project. Maybe create an interfaces directory. Then import it to your contract:

import "../interfaces/IERC20.sol";

in order to call a contract method, you always need ABI. Since you imported the file into the contract, IERC721 will be globally available in your contract. In order to call transferFrom you need to pass 3 arguments. "from address", "to address", and amount. An example of how to use it will be like this

function stakeTokens(uint256 _amount,address _token) public{
    // add require staments
    // IERC20(_token) this will initialize the contract
    IERC20(_token).transferFrom(msg.sender,address(this),_amount);
 }

Answer 2

In order to interact with an ERC20 token, you have to create an instance of it from the desired contract. You would need to import ERC20 to your nfts contracts, and then create an ERC20 token instance pointing to your token. It would be something like this:

// Inside the nfts contract
ERC20 token = ERC20("your token address here");

And then you will be able to interact with that token as:

token.transferFrom("args");

Hope you find this information useful:)