Send Tax amout to Wallet Address: Gas issue

Smart Contracts
1

Hi Guys. I'm trying to create a smart contract that receives and amount of ETH, calculates the tax and sends it to a hard coded wallet and returns the balance to user. Im constantly running into issues in respect to gas. I try to calculate this upfront. Any help or assistance would be really appreciated,
/ SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract TaxedWallet {
address payable public taxCollector = payable(0x2795377b509E5CAb8F768851F7448ecf2A758c74);

event PaymentReceived(address indexed sender, uint256 value, uint256 taxAmount, uint256 gasCost);

function sendPayment() external payable {
    require(msg.value > 0, "Amount must be greater than 0");

    uint256 taxPercentage = 2;  // Set your desired tax percentage
    uint256 taxAmount = (msg.value * taxPercentage) / 100;

    uint256 gasCost = tx.gasprice * gasleft();  // Calculate the gas cost

    uint256 amountToTransfer = msg.value - taxAmount - gasCost;

    taxCollector.transfer(taxAmount);
    payable(msg.sender).transfer(amountToTransfer);

    emit PaymentReceived(msg.sender, msg.value, taxAmount, gasCost);
}

}

2

What msg.value are you passing?

It must be large enough to ensure that msg.value - taxAmount - gasCost >= 0.

1 Like
3

Why are you considering the gas cost too?

4

All error message to gas issues, I cant even get the simplest code to work which is becoming super frustrating.

The following both fail

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract SimpleFee
{
address payable feeCollector = payable(0xDFCAb22C163EC9f1412B91f2f18a2575733F6967);

function deposit() external payable
{
require(msg.value > 0, "Amount must be greater than 0");
feeCollector.transfer(msg.value);
}
}

Modified code to consider Gas

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract SimpleFee
{
address payable feeCollector = payable(0xDFCAb22C163EC9f1412B91f2f18a2575733F6967);

function deposit() external payable
{
require(msg.value > 0, "Amount must be greater than 0");
feeCollector.transfer(msg.value - (tx.gasprice * gasleft()));
}
}

5

image.png
image.png1366×768 156 KB

6

Transfer and send are limited to 2300 gas.
Use call instead

(bool sent, bytes memory data) = feeCollector.call{gas :10000, value: msg.value}(“”)

Also the gas is taken from the sending tx.gas, why would you remove the gas for the transfer from the msg.value?

7

Hi implemented the suggested change an it stills falls over, any ideas?

image.png
image.png1366×768 158 KB

/ SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract SimpleFee {
address payable feeCollector = payable(0xDFCAb22C163EC9f1412B91f2f18a2575733F6967);

function deposit() external payable {
require(msg.value > 0, "Amount must be greater than 0");
(bool sent, bytes memory data) = feeCollector.call{gas: 10000, value: msg.value}("");
}
}

8

feeCollector = 0xDFCAb22C163EC9f1412B91f2f18a2575733F6967 is an externally-owned account, not a smart-contract account.

So feeCollector.transfer should work, and you don't need to use feeCollector.call (let alone specify a gas limit of 10000).

For further assistance, please verify your contract on Etherscan.

9

Thanks for you help, what would the complete code be then? Because I've used that previous with no joy.

10

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

contract SimpleFee
{
address payable feeCollector = payable(0xDFCAb22C163EC9f1412B91f2f18a2575733F6967);

function deposit() external payable
{
require(msg.value > 0, "Amount must be greater than 0");
feeCollector.transfer(msg.value);
}
}

11

pragma solidity ^0.8.0;

contract SimpleFee
{
address payable feeCollector = payable(0xDFCAb22C163EC9f1412B91f2f18a2575733F6967);

function deposit() external payable
{
require(msg.value > 0, "Amount must be greater than 0");
feeCollector.transfer(msg.value);
}
}

12

In order for others to be able to investigate why your transaction reverts.

You can start here.