Manage networks

Manage networks (EVM) — detect, listen, switch and add chains (EIP‑1193 compatible)

This guide shows how to detect the current network, react to chainChanged, and request switching/adding networks via the EIP‑1193 provider.

Detect the current network

const chainId = await provider.request({ method: 'eth_chainId' })
console.log('Current chain ID:', chainId) // e.g. 0x1 for mainnet

Listen for network changes

provider.on?.('chainChanged', (chainId) => {
  // Recreate clients or refresh state as needed
})

Switch to an existing chain

try {
  await provider.request({
    method: 'wallet_switchEthereumChain',
    params: [{ chainId: '0x1' }], // target chainId in hex string
  })
} catch (e) {
  if (e?.code === 4902) {
    // Chain not found — add it instead
  } else if (e?.code === 4001) {
    // User rejected
  } else {
    console.error(e)
  }
}

Add a new chain (if missing)

await provider.request({
  method: 'wallet_addEthereumChain',
  params: [{
    chainId: '0x89',
    chainName: 'Polygon',
    rpcUrls: ['https://polygon-rpc.com'],
    nativeCurrency: { name: 'MATIC', symbol: 'MATIC', decimals: 18 },
    blockExplorerUrls: ['https://polygonscan.com/'],
  }],
})

Tips

• Always use 0x‑prefixed hex strings for chainId

• Handle common error codes: 4001 (user rejected), 4902 (unknown chain)

• Reset cached state after switching chains to avoid stale data

• For non‑EVM chains (NEAR/Solana), see their dedicated sections