ERC721 批准智能合約並從中發送交易

我正在開發 ERC721。我希望 NFT 獲得批准並進行交易。當我呼叫 getApproved() 時，地址是智能合約地址，但是當我嘗試通過呼叫 safeTransferFrom() 方法進行交易時，它不起作用。我認為這可能是因為合約地址不是 EOA，你不能為智能合約支付 gas 費。但是交易所上的交易也由智能合約管理，它是如何工作的？我需要創建第二個智能合約嗎？

問候盧卡

如果我理解您的問題，您希望將 ERC721 交易從合約發送到另一個合約地址，並且您在發件人合約上使用 approve() 和 safeTransferFrom() 方法。所以你需要在接收者合約中實現 onERC721Received() 方法。看這個例子

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol";


contract Sender is ERC721 {
   
   using Counters for Counters.Counter;
   Counters.Counter private _tokenIdCounter;
   
   address public receiver;

   constructor(  ) ERC721("shx", "shx") {
   }
   
   
   function createNFT(address _receiver) public returns (uint) {
       require(_receiver != address(0), "Shx: zero address");
       receiver = _receiver;
       _tokenIdCounter.increment();
       uint256 tokenId = _tokenIdCounter.current();
       _mint(msg.sender, tokenId);
       approve(receiver, tokenId);
       // or you could use:  setApprovalForAll(b, true)
       // setApprovalForAll(b, true);
       return tokenId;
   }
   
    function createNFT2(address _receiver) public returns (uint) {
       receiver = _receiver;
       _tokenIdCounter.increment();
       uint256 tokenId = _tokenIdCounter.current();
       _mint(msg.sender, tokenId);
       setApprovalForAll(receiver, true);
       return tokenId;
   }
   
   function sendTokenToSC(uint256 tokenId) public returns(bool){
       safeTransferFrom(msg.sender, receiver, tokenId);
       return true;
   }

}

contract Receiver is  IERC721Receiver{
   address public contractSenderAddress;

    function first( address _nft) public {
        contractSenderAddress = _nft;
        
    }
    
    function ownerOf(uint256 tokenId ) public view returns(address) {
         return IERC721(contractSenderAddress).ownerOf( tokenId);
         
    } 
 
   
   function onERC721Received(address , address , uint256 , bytes memory) external pure override returns (bytes4){
       return bytes4(keccak256("onERC721Received(address,address,uint256,bytes)"));
   }
   
   
}

引用自：https://ethereum.stackexchange.com/questions/109785