Converting bytes32 to bytes4

Question

I am calling a solidity function which returns a byte4 value through web3, which returns the current string:

0x15fb397c00000000000000000000000000000000000000000000000000000000

I need to convert this string to bytes4. Will truncating it be a "safe" way?

thefett · Accepted Answer · 2022-04-29 13:00:51Z

0

Yup, thats what I do. Just take the first guys and chop off the rest.

answered Apr 29, 2022 at 13:00

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aakash4dev · Accepted Answer · 2022-05-01 05:46:02Z

With Javascript:

const 4ByteCode="0x15fb397c00000000000000000000000000000000000000000000000000000000".slice(0,10) // 0x15fb397c

it will give bytes 4 , its all safe.

Agus Velez · Accepted Answer · 2024-08-30 16:25:02Z

each byte is represented as 2 characters so you could use this function:

function parseBytes(data, numberOfBytes) { return data.slice(0, numberOfBytes * 2); }

3 Answers 3