检测发送到合约的 ERC20 代币 -？

Question

I'm developing a game. Energy will be purchased with my own token.

For example, to buy energy, you will use the "X" token you purchased earlier. It's like buying 1 energy for 1000 "X" tokens.

I searched a lot but couldn't find an answer.

I'm looking for a function just like receive() does.

I want to add the amount of XXXX tokens sent to the contract and the wallet address that sent these tokens to a mapping and update the energy count.

For example, the user has sent 1000 X tokens (X is representative only). The amount of X tokens sent will be recorded with the sending wallet: Example: mapping(address => uint) xTokenInfo;

And for every 1000 X tokens, energy will be given to the wallet that sent the token.

For example: Let's say 10,000 (10K) X tokens are sent. That means 10 energy.

SAMPLE:

address currentTokenAddress = 0xTOKEN;

mapping(address => uint) energyBalance;

function sendToken_and_ConvertEnergys(uint _tokenAmount){
  if(sentToken == currentTokenAddress){
    energyBalance[msg.sender] = (_tokenAmount/1000);
  } else {
    revert("Only X TOKENs are accepted");
 }
}

Answer 1

You need to use Standard ERC20 interface in your contract to transfer X token and in order to do so, you need to let your users to approve the same amount of token prior to it (Approve is usually done through the UI).

Try this:

interface IERC20 {
   function transferFrom(address sender, address recipient, uint amount) external returns(bool);
   /* rest of the method */
}

contract Energy {
   address currentTokenAddress public = 0xTOKEN;
   mapping(address => uint) energyBalance;

   function sendToken_and_ConvertEnergys(uint _tokenAmount) external {
       uint calculatedEnergy = _tokenAmount/1000;
       IERC20(currentTokenAddress ).transferFrom(msg.sender,address(this),calculatedEnergy);
       energyBalance[msg.sender] += _calculatedEnergy;
  }
}