How to Wrap and Unwrap Tokens

This guide provides step-by-step instructions on how to wrap and unwrap tokens for use in our betting system on the Gnosis Chain and Base Chain. Wrapping tokens ensures compatibility with our smart contracts.

What is a Wrapped Token?

A wrapped token is a tokenized version of an existing cryptocurrency that is compatible with a specific blockchain or protocol. In our case, these include:

• WXDAI (opens in a new tab): Wrapped XDAI (ERC-20 version of native XDAI) for Gnosis Chain.
• WETH (opens in a new tab): Wrapped ETH (ERC-20 version of native ETH) for Base Chain.

Official contracts

Always ensure you're using the official wrapped token contract addresses:

• WXDAI: 0xe91D153E0b41518A2Ce8Dd3D7944Fa863463a97d (opens in a new tab)
• WETH: 0x4200000000000000000000000000000000000006 (opens in a new tab)

How to Wrap Your Native Tokens

wagmi/viem XDAI example

import { createWalletClient, encodeFunctionData } from 'viem'
 
const abi = [
  {
    'constant': false,
    'inputs': [],
    'name': 'deposit',
    'outputs': [],
    'payable': true,
    'stateMutability': 'payable',
    'type': 'function',
  },
] as const
 
const walletClient = createWalletClient({...})
 
await walletClient.sendTransaction({ 
  account: '0xsdk....',
  to: '0xe91D153E0b41518A2Ce8Dd3D7944Fa863463a97d',
  value: 1000000000000000000n,
  data: encodeFunctionData({
    abi: abi,
    functionName: 'deposit',
  }),
})

The wrapped token contract provides a deposit method to convert native tokens. Follow these steps:

1. Visit the official wrapped token contract on a blockchain explorer:
   • Gnosis Chain WXDAI (opens in a new tab)
   • Base Chain WETH (opens in a new tab)

2. Connect your web3 wallet and navigate to the deposit function.:

3. Enter the amount of native tokens you want to wrap and click the Write button:

4. Once the transaction is confirmed, your native tokens will be converted, and you will receive the equivalent amount in wrapped tokens.

How to Unwrap Tokens

wagmi/viem XDAI example

import { createWalletClient, encodeFunctionData } from 'viem'
 
const abi = [
  {
    "constant": false,
    "inputs": [
      {
        "name": "wad",
        "type": "uint256"
      }
    ],
    "name": "withdraw",
    "outputs": [],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function"
  },
] as const
 
const walletClient = createWalletClient({...})
 
await walletClient.sendTransaction({ 
  account: '0xsdk....',
  to: '0xe91D153E0b41518A2Ce8Dd3D7944Fa863463a97d',
  data: encodeFunctionData({
    abi: abi,
    functionName: 'withdraw',
    args: [ 1000000000000000000n ],
  }),
})

The wrapped token contract provides a withdraw method to unwrap tokens and convert them back to native tokens, follow these steps:

1. Visit the official wrapped token contract on a blockchain explorer:
   • Gnosis Chain WXDAI (opens in a new tab)
   • Base Chain WETH (opens in a new tab)

2. Connect your wallet and navigate to the withdraw function.

3. Enter the amount of wrapped tokens you want to unwrap and click the Write button.

4. Once the transaction is confirmed, your wrapped tokens will be converted back to native tokens.