Ethers.js Number Conversion – How to Convert Number to Bytes in Ethers.js?

bytes32ethers.jshardhatuint256

I have a number in javascript:

const oracleResponse = 1

And I have a function that takes a bytes32 as input parameters

function fulfillOracleRequest(
    bytes32 _requestId,
    bytes32 _data
  )

I want to convert oracleResponse in javascript to its bytes edition so that I can call this function. How do I do this?

*Note: const oracleResponse = ethers.utils.hexlify(1) will not work, since this will return 0x1 which is the incorrect length.

Best Answer

ethers also has a padding function where it will add the zeros to make it the correct length. It looks like this

const oracleResponse = ethers.utils.hexZeroPad(ethers.utils.hexlify(1), 32)

This will pad your result to be length 32, and allow it to be accepted by your function.

Related Solutions

Solidity String Conversion – How to Convert a String to Bytes32

This has worked for me so far. Not sure if it's the best way.

function stringToBytes32(string memory source) public pure returns (bytes32 result) {
    bytes memory tempEmptyStringTest = bytes(source);
    if (tempEmptyStringTest.length == 0) {
        return 0x0;
    }

    assembly {
        result := mload(add(source, 32))
    }
}

Also, remember that strings in solidity are UTF8 so after converting them to bytes each byte is not necessarily a character.

EDIT: shorter version, should work the same.

Solidity Bytes32 – Convert Bytes32 to Ordered Bytes2, Bytes4, and More

Your question is not clear enough. When you want to split 32 bytes into 5 variables that have a total length of 2+2+2+2+8+1 = 17 you should specify what bytes you want to be chunked (bytes from left or bytes from right).

I wrote an example that solves your problem as far as I could understand it. Comment the answer - explain what you exactly need, and I'll change the code.

pragma solidity ^0.4.0;

contract BytesChunkTest
{
    bytes32 constant public test_source=0x000000000000000000ff11223344556677889900aabbccddeeff;

    bytes32 constant mask1 = 0xff00000000000000000000000000000000000000000000000000000000000000;
    bytes32 constant mask2 = 0xffff000000000000000000000000000000000000000000000000000000000000;
    bytes32 constant mask8 = 0xffffffffffffffff000000000000000000000000000000000000000000000000;
    uint    constant main_shift=15;

    function sourceToChunk(bytes32 source) constant
    returns
        (
            bytes2 r1_2,
            bytes2 r2_2,
            bytes2 r3_2,
            bytes2 r4_2,
            bytes8 r5_8,
            bytes1 r6_1
        )
    {

        r1_2 = bytes2(source<<(main_shift*8)&mask2);
        r2_2 = bytes2((source<<(main_shift+2)*8)&mask2);
        r3_2 = bytes2((source<<(main_shift+4)*8)&mask2);
        r4_2 = bytes2((source<<(main_shift+6)*8)&mask2);
        r5_8 = bytes8((source<<(main_shift+8)*8)&mask8);
        r6_1 = bytes1((source<<(main_shift+16)*8)&mask1);
    }


    function test() constant
    returns
        (
            bytes2,
            bytes2,
            bytes2,
            bytes2,
            bytes8,
            bytes1
        )
    {
        return sourceToChunk(test_source);
    }
}

Best Answer

Related Solutions

Solidity String Conversion – How to Convert a String to Bytes32

Solidity Bytes32 – Convert Bytes32 to Ordered Bytes2, Bytes4, and More

Related Topic