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Ethereum / EVM

Use the injected EIP-1193 provider to build EVM dApps with OneKey. All EVM-compatible chains (Ethereum, Polygon, BSC, Arbitrum, Optimism, Base, etc.) share the same provider.

Provider Detection

EIP-6963 (Recommended)

Modern multi-wallet detection that avoids conflicts:


let onekeyProvider = null
const onAnnounce = (event) => {
  if (event.detail.info.rdns === 'so.onekey.app.wallet') {
    onekeyProvider = event.detail.provider
  }
}
window.addEventListener('eip6963:announceProvider', onAnnounce)
window.dispatchEvent(new Event('eip6963:requestProvider'))
 
// Call from your Connect button after the user selects OneKey.
async function connectOneKey() {
  if (!onekeyProvider) throw new Error('OneKey has not announced a provider yet')
  return onekeyProvider.request({ method: 'eth_requestAccounts' })
}
// On component cleanup:
// window.removeEventListener('eip6963:announceProvider', onAnnounce)

Direct Access (Fallback)


const provider = window.$onekey?.ethereum
if (!provider) throw new Error('OneKey not detected')
 
const accounts = await provider.request({ method: 'eth_requestAccounts' })

Events


// Account changed
provider.on('accountsChanged', (accounts) => {
  console.log('Account:', accounts[0])
})
 
// Network changed
provider.on('chainChanged', (chainId) => {
  console.log('Chain:', chainId)
  window.location.reload() // Recommended
})
 
// Connected
provider.on('connect', (info) => {
  console.log('Connected to chain:', info.chainId)
})

Error Codes

Code	Description	Solution
4001	User rejected	Handle rejection gracefully
4902	Unknown chain	Add chain with `wallet_addEthereumChain`
-32602	Invalid params	Use `0x`-prefixed hex strings
-32603	Internal error	Check request format

Chain IDs

Network	Chain ID	Hex
Ethereum Mainnet	1	0x1
Polygon	137	0x89
BSC	56	0x38
Arbitrum One	42161	0xa4b1
Optimism	10	0xa
Base	8453	0x2105

See chainlist.org for more chains.

For quick integration with UI components, use RainbowKit or Web3Modal.