3

I simply want to create a 32 byte hash of a string and compare equality to another one, but this is proving almost impossible for some reason. E.g:

hash("a") == hash("b")

My compiler throws errors if I try to use keccak256: TypeError: Invalid type for argument in function call. Invalid implicit conversion from string memory to bytes memory requested. This function requires a single bytes argument as this only seems to be able to take bytes memory. Hashes created by abi.encode are not comparable with == and are also not of a fixed length it seems so this also doesn't seem to be a solution.

I am new to programming in Solidity, so any help would be great; I am using solidity 0.5.0!

2

Try this:

pragma solidity 0.5.1;

contract Hasher {

    function compare(string memory a, string memory b) public pure returns(bool) {
        return keccak256(abi.encodePacked(a)) == keccak256(abi.encodePacked(b));
    }
}

Hope it helps.

  • Can we do directly keccak256(a) == keccak256(b) ? @Rob Hitchens B9lab – alper Feb 21 at 9:34

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