Right now I'm getting a weird error, I'm trying to convert an object to a string and I get this type error.

const x = await web3.eth.getTransaction(tx);
               
console.log(x);
        ^
    Console Output:
{
  blockHash: '0x000ef0000abf000d0f000e0ff000c000a00d750d066ea0c60a00f0000b0f000c0',
  blockNumber: 0n,
  from: '0x0c000f0e0c000e000bfbc0c002000c0b0ec100000',
  gas: 0n,
  gasPrice: 0n,
  maxFeePerGas: 0n,
  maxPriorityFeePerGas: 0n,
  hash: '0x000000000000000d00f000f0000ffa000bd000c00cc0000b0fd000a0a00ffccfc',
  input: '0x',
  nonce: 0n,
  to: '0x000d0aa0fa0000ef00b00cb0e0000d000c0a00e0',
  transactionIndex: 0n,
  value: 0n,
  type: 0n,
  accessList: [],
  chainId: 0n,
  v: 0n,
  r: '0xa0000f00000f00c0b000000bffc000000000a000000000cc00e000100aa0d0d0',
  s: '0x0c0f00ec0cf0df0eb0000e00bce0000d00b0000a0000ffae0cc0ef28000e0cc',
  data: '0x'
}

But then I try to convert x into a string:

JSON.stringify(recoverTransaction)
     ^
    TypeError: Do not know how to serialize a BigInt

Right now I'm getting a weird error, I'm trying to convert an object to a string and I get this type error.

const x = await web3.eth.getTransaction(tx);
               
console.log(x);
        ^
    Console Output:
{
  blockHash: '0x000ef0000abf000d0f000e0ff000c000a00d750d066ea0c60a00f0000b0f000c0',
  blockNumber: 0n,
  from: '0x0c000f0e0c000e000bfbc0c002000c0b0ec100000',
  gas: 0n,
  gasPrice: 0n,
  maxFeePerGas: 0n,
  maxPriorityFeePerGas: 0n,
  hash: '0x000000000000000d00f000f0000ffa000bd000c00cc0000b0fd000a0a00ffccfc',
  input: '0x',
  nonce: 0n,
  to: '0x000d0aa0fa0000ef00b00cb0e0000d000c0a00e0',
  transactionIndex: 0n,
  value: 0n,
  type: 0n,
  accessList: [],
  chainId: 0n,
  v: 0n,
  r: '0xa0000f00000f00c0b000000bffc000000000a000000000cc00e000100aa0d0d0',
  s: '0x0c0f00ec0cf0df0eb0000e00bce0000d00b0000a0000ffae0cc0ef28000e0cc',
  data: '0x'
}

But then I try to convert x into a string:

JSON.stringify(recoverTransaction)
     ^
    TypeError: Do not know how to serialize a BigInt

• javascript
• json
• string
• ethereum
• web3js

• 1 BigInt is not one of the valid JSON datatypes, you can't use JSON.stringify() to convert it to a string. – Barmar Commented Mar 24 at 1:24
• 1 Check stackoverflow/questions/65152373/serialize-bigint-in-json – James Commented Mar 24 at 1:29

1 Answer 1

I solved with this function:

• Checks if the value is of type bigint and converts it to a string using value.toString().
• Non-bigint values remain unchanged.

JSON.stringify(x, (key, value) =>
    typeof value === 'bigint' ? value.toString() : value
);

The transaction object is now successfully serialized as a JSON string, with all BigInt values represented as strings.