Skip to content
On this page

encodeAbiParameters โ€‹

Generates ABI encoded data using the ABI specification, given a set of ABI parameters (inputs/outputs) and their corresponding values.

The encodeAbiParameters function is used by the other contract encoding utilities (ie. encodeFunctionData, encodeEventTopics, etc).

Import โ€‹

ts
import { encodeAbiParameters } from 'viem'

Usage โ€‹

The encodeAbiParameters function takes in two parameters:

  • a set of ABI Parameters (params), that can be in the shape of the inputs or outputs attribute of an ABI Item.
  • a set of values (values) that correspond to the given params.
ts
import { encodeAbiParameters } from 'viem'

const encodedData = encodeAbiParameters(
  [
    { name: 'x', type: 'string' },
    { name: 'y', type: 'uint' },
    { name: 'z', type: 'bool' }
  ],
  ['wagmi', 420n, true]
)
// 0x000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000001a4000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000057761676d69000000000000000000000000000000000000000000000000000000

Human Readable โ€‹

You can also pass in Human Readable parameters with the parseAbiParameters utility.

ts
import { encodeAbiParameters, parseAbiParameters } from 'viem'

const encodedData = encodeAbiParameters(
  parseAbiParameters('string x, uint y, bool z'),
  ['wagmi', 420n, true]
)
// 0x000000000000000000000000000000000000000000000000000000000000006000000000000000000000000000000000000000000000000000000000000001a4000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000000057761676d69000000000000000000000000000000000000000000000000000000

Returns โ€‹

Hex

The ABI encoded data.

Parameters โ€‹

params โ€‹

The set of ABI parameters to encode, in the shape of the inputs or outputs attribute of an ABI event/function.

These parameters must include valid ABI types.

ts
encodeAbiParameters(
  [{ name: 'x', type: 'uint32' }], 
  [69420]
)

values โ€‹

The set of primitive values that correspond to the ABI types defined in params.

ts
encodeAbiParameters(
  [{ name: 'x', type: 'uint32' }],
  [69420] 
)

More Examples โ€‹

Simple struct โ€‹

ts
import { abi } from './abi'

const encodedData = encodeAbiParameters(
  abi[0].inputs,
  [{
    x: 420n,
    y: true,
    z: '0xa5cc3c03994DB5b0d9A5eEdD10CabaB0813678AC',
  }],
)
// 0x00000000000000000000000000000000000000000000000000000000000001a40000000000000000000000000000000000000000000000000000000000000001000000000000000000000000a5cc3c03994db5b0d9a5eedd10cabab0813678ac
ts
export const abi = [
  {
    name: 'staticStruct',
    inputs: [
      {
        components: [
          {
            name: 'x',
            type: 'uint256',
          },
          {
            name: 'y',
            type: 'bool',
          },
          {
            name: 'z',
            type: 'address',
          },
        ],
        name: 'foo',
        type: 'tuple',
      },
    ],
  }
] as const
solidity
contract Example {
  struct Foo {
    uint256 x;
    bool y;
    address z;
  }

  function staticStruct(Foo calldata foo) { ... }
}

Released under the MIT License.