Extensions

Extensions let interact with common standards (such as ERC20, ERC721, ERC1155, etc.) in a more convenient way. You can use the built-in extensions or create your own.

To use an extension, you just need to import it and call it with the necessary parameters.

import { getContract } from "thirdweb";
import { balanceOf } from "thirdweb/extensions/erc20";
 
// get the contract
const contract = getContract({...});
 
// call the extension function
const balance = await balanceOf({
	contract,
	address: "0x5678...",
});

import { getContract, sendTransaction } from "thirdweb";
import { transfer } from "thirdweb/extensions/erc20";
 
// get the contract
const contract = getContract({...});
 
// call the extension function to prepare the transaction
const transaction = transfer({
  contract,
  to: "0x1234...",
  amount: "1",
});
 
// send the transaction
const transactionResult = await sendTransaction({
  transaction,
  wallet,
});

You can create your own extensions. They are just regular functions that pre-define the behavior of a prepareContractCall() or readContract() function.

import { readContract, type BaseTransactionOptions } from "thirdweb";
 
// define your extension function
export function balanceOf(
  // the base options include everything that is needed to interact with the contract, *except* the specific params for your function, in this case "address"
  options: BaseTransactionOptions<{ address: string }>,
) {
  return readContract({
    // pass the contract from the options
    contract: options.contract,
    // pre-define the function that `balanceOf()` will call on the smart contract
    method: "function balanceOf(address) returns (uint256)",
    // pass the params from the options
    params: [options.address],
  });
}

import {
  prepareContractCall,
  type BaseTransactionOptions,
} from "thirdweb";
 
// define your extension function
export function transfer(
  // the base options include everything that is needed to interact with the contract, *except* the specific params for your function, in this case "to" and "amount"
  options: BaseTransactionOptions<{ to: string; amount: bigint }>,
) {
  return prepareContractCall({
    // pass the contract from the options
    contract: options.contract,
    // pre-define the function that `transfer()` will call on the smart contract
    method: "function transfer(address, uint256)",
    // pass the params from the options
    params: [options.to, options.amount],
  });
}