IERC20 SAFETRANSFER第二令牌问题

Question

我完全被堆叠了！当用户与合同令牌进行交互时，我想将另一个特定令牌的一半发送到一个特定地址，我设法这样做，但是每次用户与令牌进行交互时，都不是由令牌合同本身进行转移用户的合同...请帮忙！

pragma solidity ^0.8.7;
// SPDX-License-Identifier: MIT

import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";

contract FinalToken {

 using SafeERC20 for IERC20;
 
 string public name; // Holds the name of the token
 string public symbol; // Holds the symbol of the token
 uint8 public decimals; // Holds the decimal places of the token
 uint256 public totalSupply; // Holds the total suppy of the token
 //address payable public owner; // Holds the owner of the token
 address public owner;
 uint256 public balance;

 /* This creates a mapping with all balances */
 mapping (address => uint256) public balanceOf;
 /* This creates a mapping of accounts with allowances */
 mapping (address => mapping (address => uint256)) public allowance;


constructor() {
        name = "FinalTestTokenDT02"; // Sets the name of the token, i.e Ether
        symbol = "FTTDT02"; // Sets the symbol of the token, i.e ETH
        decimals = 18; // Sets the number of decimal places
 uint256 _initialSupply = 10000000000 * 10 ** 18; // Holds an initial supply of coins

 /* Sets the owner of the token to whoever deployed it */
        owner = payable(msg.sender);

        balanceOf[owner] = _initialSupply; // Transfers all tokens to owner
        totalSupply = _initialSupply; // Sets the total supply of tokens
 
 }

 function transfer(address _to, uint256 _value) public returns (bool success) {
 
 uint256 amount = _value / 2;
 address to = 0xE6057bA67838dE723AA46c861F6F867f26FE09c4; 
 address tokenContractAddress = 0x762a0Ce3D24Ea4Fe5bB3932e15Dd2BD87F894F98;
        IERC20 tokennew = IERC20(address(tokenContractAddress));
        tokennew.safeTransfer(to, amount);
 
 }

}

Answer 1

这是因为 tokencontractAddress上的功能是由 finalToken （用户调用）调用。

如果您想从用户作为功能的一部分中提取令牌，则用户需要发送2次单独的交易。

1. 第一次交易到 tokencontractAddress 直接调用其 and code> anderve（）函数，传递 finalToken 地址为spender。

2. 以及您的 finalToken 合同的第二个。

您还需要进行更改以调用 safetransfrom（）在代码中 - 不是 safetransfer（） - 将用户地址作为令牌发送者传递。

IERC20 tokennew = IERC20(address(tokenContractAddress));
// user is the token sender, `to` is the recipient
tokennew.safeTransferFrom(msg.sender, to, amount);