Best Practice to handle big number

Question

i have erc20 token with 18 decimal, the problem is if i want to transfer 100k token, the javascript can't handle that, because there will lot of 0.

so in smart contract i override all the transfer function into this

function transfer(address _toadr, uint256 _amount) override public returns (bool) {
    uint transferedAmount = _amount*10**18;
    uint balance =address(msg.sender).balance *10**18;
    require(balance >= transferedAmount);
    
    uint256 _teamFee = (transferedAmount / 100) * teamFee; 
    uint256 _marketingFee = (transferedAmount / 100) * marketingFee; 
    uint256 _rewardFee = (transferedAmount / 100) * rewardFee;
    uint256 _finalAmount = transferedAmount-(_teamFee+_marketingFee+_rewardFee);

    _transfer(msg.sender,team,_teamFee);
    _transfer(msg.sender,marketing,_marketingFee);
    _transfer(msg.sender,rewardpool,_rewardFee);
    _transfer(msg.sender,_toadr,_finalAmount);

    return true;
}

is this safe to do? or is there a best practice for this?

i heard we can use some utils from web3.js, but i didn't find a way to compare 2 value if i use web3.js utils.

Answer 1

You should use some BigNumber library. web3js has BN for that: https://web3js.readthedocs.io/en/v1.2.11/web3-utils.html#bn

With BN you can do calculations and comparisons with big numbers. You definitely should not change your Solidity because of big numbers.