Check division is integer or float solidity

Question

Suppose i have a contract with decimals and total Supply as follow. How can i check if tokenAmountInWei pass in is integer value in form of ether.

decimals = 18
totalSupply = 1000000

function someFunction(uint tokenAmountInWei) {
    // check if tokenAmountInWei convert to ether is integer value
}

Answer 1

This should work:

pragma solidity ^0.4.24;

contract Test {

    function checkIntegerETH(uint a) public pure returns (bool) {
        return (a % 1 ether == 0);
    }
}

Here we are basically confirming that a has no remainder when being divided by 10¹⁸ (1 ether).